Beispiel #1
0
    def rx_work(self, ser):
        while 1:
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if not pmt.pmt_is_blob(msg.value):
                continue

            blob = pmt.pmt_blob_data(msg.value)

            tx_string = pmt.pmt_blob_data(msg.value).tostring()

            ser.write(tx_string)
Beispiel #2
0
    def rx_work(self, ser):
        while (1):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if not pmt.pmt_is_blob(msg.value):
                continue

            blob = pmt.pmt_blob_data(msg.value)

            tx_string = pmt.pmt_blob_data(msg.value).tostring()

            ser.write(tx_string)
    def work(self, input_items, output_items):
		
		while(1):
			try: msg = self.pop_msg_queue()
			except: return -1
			
			if not pmt.pmt_is_blob(msg.value): 
				print self.addr
				print "not a blob - simple mac"
				continue
			
			self.key_string = pmt.pmt_symbol_to_string(msg.key)
			self.value = pmt.pmt_blob_data(msg.value)
            
            
			if(msg.offset == 0):
				if (len(self.value) > 0):
					if(self.value[0] == 0):
						self.channel_state = READY
					else:
						self.channel_state = NOT_READY
		
			if(msg.offset == 1):
				self.q.put(msg)
				if(self.channel_state == NOT_READY): print 'hold back'
				
			if (self.channel_state == READY):
				while not self.q.empty():
					self.q.get()
					self.post_msg(0, msg)
    def work(self, input_items, output_items):

        while (1):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if not pmt.pmt_is_blob(msg.value):
                print self.addr
                print "not a blob - simple mac"
                continue

            self.key_string = pmt.pmt_symbol_to_string(msg.key)
            self.value = pmt.pmt_blob_data(msg.value)

            if (msg.offset == 0):
                if (len(self.value) > 0):
                    if (self.value[0] == 0):
                        self.channel_state = READY
                    else:
                        self.channel_state = NOT_READY

            if (msg.offset == 1):
                self.q.put(msg)
                if (self.channel_state == NOT_READY): print 'hold back'

            if (self.channel_state == READY):
                while not self.q.empty():
                    self.q.get()
                    self.post_msg(0, msg)
Beispiel #5
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    def work(self, input_items, output_items):
        """
        For each message we receive, we generate for each of its
        bits a uniformly distributed random number and see if it
        is smaller than the threshold given by BER.
        """
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1

            if not pmt.pmt_is_blob(msg.value):
                print '[%s] not a blob' % self.name()
                continue

            if msg.offset == 0:
                data = pmt.pmt_blob_data(msg.value)
                for b in range(self.bits_per_byte):
                    if random.random() < self.ber:
                        data ^= (0x01 << b)
                blob = self.mgr.acquire(True)
                pmt.pmt_blob_resize(blob, len(data))
                pmt.pmt_blob_rw_data(blob)[:] = data
                self.post_msg(0, pmt.pmt_string_to_symbol('U'), blob)

            else:
                print '[%s] w00t, weird msg offset' % self.name()
Beispiel #6
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 def send_pkt_radio(self, msg, pkt_cnt, dest, protocol_id, control):
     pkt_str = chr(pkt_cnt) + chr(self.addr) + chr(dest) + chr(
         protocol_id) + chr(control) + pmt.pmt_blob_data(
             msg.value).tostring()
     blob = self.mgr.acquire(True)  #block
     pmt.pmt_blob_resize(blob, len(pkt_str))
     pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(pkt_str,
                                                      dtype='uint8')
     self.post_msg(0, pmt.pmt_string_to_symbol('U'), blob)
     return
Beispiel #7
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    def work(self, input_items, output_items):
        
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1
            
            print  
    
            if not pmt.pmt_is_blob(msg.value): 
                print "BTW, this not a blob"
                print "Key: ",pmt.pmt_symbol_to_string(msg.key),"Value: ",pmt.pmt_symbol_to_string(msg.key)

            else:
                print "Key: ",pmt.pmt_symbol_to_string(msg.key),"Value: ",pmt.pmt_blob_data(msg.value).tostring()                
Beispiel #8
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    def work(self, input_items, output_items):

        while (1):  #for simplicty, we'll loop.  Blocks on self.pop call
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            #test to make sure this is a blob
            if not pmt.pmt_is_blob(msg.value):
                continue

            if msg.offset == DATA_IN:

                #recall that a pmt includes a key, source, offset, and value
                key = pmt.pmt_symbol_to_string(msg.key)
                #print "Key: ",key

                #now lets get the actual data
                blob = pmt.pmt_blob_data(msg.value)

                if blob[0] == 0:
                    tx_str = "Emitter off\n\r"
                else:
                    tx_str = "Emitter detected\n\r"

                #print "Blob Value: ",blob.tostring()

                blob = self.mgr.acquire(True)  #block
                pmt.pmt_blob_resize(blob, len(tx_str))
                pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(tx_str,
                                                                 dtype='uint8')

                self.post_msg(0, pmt.pmt_string_to_symbol("n/a"), blob,
                              pmt.pmt_string_to_symbol("rpt"))

            else:

                pkt_str = "I've seen an event"
                key_str = "event_report"
                src_str = "my_first_msg_block"

                blob = self.mgr.acquire(True)  #block
                pmt.pmt_blob_resize(blob, len(pkt_str))
                pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(pkt_str,
                                                                 dtype='uint8')

                self.post_msg(0, pmt.pmt_string_to_symbol(key_str), msg.value,
                              pmt.pmt_string_to_symbol(src_str))
    def work(self, input_items, output_items):
        
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1

            if not pmt.pmt_is_blob(msg.value): 
                print "not a blob - virtual mux"
                continue

            #insert header byte so demux can route to appropriate output
            data = numpy.concatenate([numpy.array([msg.offset]),pmt.pmt_blob_data(msg.value)])
            
            blob = self.mgr.acquire(True) #block
            pmt.pmt_blob_resize(blob, len(data))
            pmt.pmt_blob_rw_data(blob)[:] = data
            self.post_msg(0,msg.key,blob,pmt.pmt_string_to_symbol('mux')) #pass incoming key for transparency
Beispiel #10
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    def work(self, input_items, output_items):

        while (1):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            print

            if not pmt.pmt_is_blob(msg.value):
                print "BTW, this not a blob"
                print "Key: ", pmt.pmt_symbol_to_string(
                    msg.key), "Value: ", pmt.pmt_symbol_to_string(msg.key)

            else:
                print "Key: ", pmt.pmt_symbol_to_string(
                    msg.key), "Value: ", pmt.pmt_blob_data(
                        msg.value).tostring()
Beispiel #11
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    def work(self, input_items, output_items):
        
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1

            if not pmt.pmt_is_blob(msg.value):
                continue

            blob = pmt.pmt_blob_data(msg.value)
            
            if self.arq == ARQ_TRUE:
                arq_char = 'U'
            else:
                arq_char = 'V'
                
            key_str = arq_char + chr(self.channel)
            
            self.post_msg(0, pmt.pmt_string_to_symbol(key_str), msg.value)
Beispiel #12
0
    def work(self, input_items, output_items):
        
        while(1):#for simplicty, we'll loop.  Blocks on self.pop call
            try: msg = self.pop_msg_queue()
            except: return -1

            #test to make sure this is a blob
            if not pmt.pmt_is_blob(msg.value):
                continue

            if msg.offset == DATA_IN:
        
                #recall that a pmt includes a key, source, offset, and value
                key = pmt.pmt_symbol_to_string(msg.key)
                #print "Key: ",key
                
                #now lets get the actual data
                blob = pmt.pmt_blob_data(msg.value)
                
                if blob[0] == 0:
                    tx_str = "Emitter off\n\r"
                else:
                    tx_str = "Emitter detected\n\r"
                
                #print "Blob Value: ",blob.tostring()
                
                blob = self.mgr.acquire(True) #block
                pmt.pmt_blob_resize(blob, len(tx_str))
                pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(tx_str, dtype='uint8')
                
                self.post_msg(0,pmt.pmt_string_to_symbol("n/a"), blob, pmt.pmt_string_to_symbol("rpt") )
                
            else:
                
                pkt_str = "I've seen an event"
                key_str = "event_report"
                src_str = "my_first_msg_block"
                
                blob = self.mgr.acquire(True) #block
                pmt.pmt_blob_resize(blob, len(pkt_str))
                pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(pkt_str, dtype='uint8')
   
                self.post_msg(0, pmt.pmt_string_to_symbol(key_str), msg.value, pmt.pmt_string_to_symbol(src_str))
Beispiel #13
0
    def work(self, input_items, output_items):
        while not len(self._pkt):
            try: msg = self.pop_msg_queue()
            except: return -1
            if not pmt.pmt_is_blob(msg.value): continue
            pkt = packet_utils.make_packet(
                pmt.pmt_blob_data(msg.value).tostring(),
                self._samples_per_symbol,
                self._bits_per_symbol,
                self._access_code,
                False, #pad_for_usrp,
                self._whitener_offset,
            )
            self._pkt = numpy.fromstring(pkt, numpy.uint8)
            if self._use_whitener_offset:
                self._whitener_offset = (self._whitener_offset + 1) % 16

        num_items = min(len(self._pkt), len(output_items[0]))
        output_items[0][:num_items] = self._pkt[:num_items]
        self._pkt = self._pkt[num_items:] #residue for next work()
        return num_items
Beispiel #14
0
    def work(self, input_items, output_items):

        while (1):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if not pmt.pmt_is_blob(msg.value):
                print "not a blob - virtual mux"
                continue

            #insert header byte so demux can route to appropriate output
            data = numpy.concatenate(
                [numpy.array([msg.offset]),
                 pmt.pmt_blob_data(msg.value)])

            blob = self.mgr.acquire(True)  #block
            pmt.pmt_blob_resize(blob, len(data))
            pmt.pmt_blob_rw_data(blob)[:] = data
            self.post_msg(0, msg.key, blob, pmt.pmt_string_to_symbol(
                'mux'))  #pass incoming key for transparency
Beispiel #15
0
    def work(self, input_items, output_items):
        
        while(1):#for simplicty, we'll loop.  Blocks on self.pop call
            try: msg = self.pop_msg_queue()
            except: return -1

            #test to make sure this is a blob
            if not pmt.pmt_is_blob(msg.value):
                continue

            if msg.offset == DATA_IN:
        
                #recall that a pmt includes a key, source, offset, and value
                key = pmt.pmt_symbol_to_string(msg.key)
                print "Key: ",key
                
                #now lets get the actual data
                blob = pmt.pmt_blob_data(msg.value)
                
                print "Blob Value: ",blob.tostring()
                
            else:
                
                pkt_str = "I've seen an event"
                key_str = "event_report"
                src_str = "my_first_msg_block"
                
                blob = self.mgr.acquire(True) #block
                pmt.pmt_blob_resize(blob, len(pkt_str))
                pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(pkt_str, dtype='uint8')
   
                self.post_msg(DATA_OUT, pmt.pmt_string_to_symbol(key_str), msg.value, pmt.pmt_string_to_symbol(src_str))
                
                print self.freq_list[self.index]
                
                self.post_msg(CTRL_OUT,pmt.pmt_string_to_symbol('usrp_source.set_center_freq'),pmt.from_python( ( ( self.freq_list[self.index] , ), { } ) ),pmt.pmt_string_to_symbol('2nd_block'))

                self.index = ( self.index + 1 ) % self.freq_list_len
Beispiel #16
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    def work(self, input_items, output_items):
        while not len(self._pkt):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1
            if not pmt.pmt_is_blob(msg.value): continue
            pkt = packet_utils.make_packet(
                pmt.pmt_blob_data(msg.value).tostring(),
                self._samples_per_symbol,
                self._bits_per_symbol,
                self._access_code,
                False,  #pad_for_usrp,
                self._whitener_offset,
            )
            self._pkt = numpy.fromstring(pkt, numpy.uint8)
            if self._use_whitener_offset:
                self._whitener_offset = (self._whitener_offset + 1) % 16

        num_items = min(len(self._pkt), len(output_items[0]))
        output_items[0][:num_items] = self._pkt[:num_items]
        self._pkt = self._pkt[num_items:]  #residue for next work()
        return num_items
    def work(self, input_items, output_items):
        
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1
            
            if not pmt.pmt_is_blob(msg.value): 
                print "not a blob - virtual demux"
                continue

            incoming_array = pmt.pmt_blob_data(msg.value)
            outgoing_array = incoming_array[1:]
            
            output_port = int(incoming_array[0])

            #check to make sure the byte header is within our valid range
            if  ( output_port > ( self.port_count - 1 ) ):
                print 'received msg outside of port range'
                continue

            blob = self.mgr.acquire(True) #block
            pmt.pmt_blob_resize(blob, len(outgoing_array))
            pmt.pmt_blob_rw_data(blob)[:] = outgoing_array
            self.post_msg(output_port,pmt.pmt_string_to_symbol('n/a'),blob,pmt.pmt_string_to_symbol('demux'))
Beispiel #18
0
    def tx_frames(self):
        #send_sob
        #self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('tx_sob'), pmt.PMT_T, pmt.pmt_string_to_symbol('tx_sob'))

        #get all of the packets we want to send
        total_byte_count = 0
        frame_count = 0

        #put residue from previous execution
        if self.has_old_msg:
            length = len(pmt.pmt_blob_data(self.old_msg.value)) + self.overhead
            total_byte_count += length
            self.tx_queue.put(self.old_msg)
            frame_count += 1
            self.has_old_msg = False
            print 'old msg'

        #fill outgoing queue until empty or maximum bytes queued for slot
        while (not self.queue.empty()):
            msg = self.queue.get()
            length = len(pmt.pmt_blob_data(msg.value)) + self.overhead
            total_byte_count += length
            if total_byte_count >= self.bytes_per_slot:
                self.has_old_msg = True
                self.old_msg = msg
                print 'residue'
                continue
            else:
                self.has_old_msg = False
                self.tx_queue.put(msg)
                frame_count += 1

        time_object = int(math.floor(
            self.antenna_start)), (self.antenna_start % 1)

        #if no data, send a single pad frame
        #TODO: add useful pad data, i.e. current time of SDR
        if frame_count == 0:
            data = self.pad_data
            more_frames = 0
            tx_object = time_object, data, more_frames
            self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('full'),
                          pmt.from_python(tx_object),
                          pmt.pmt_string_to_symbol('tdma'))
        else:
            #print frame_count,self.queue.qsize(), self.tx_queue.qsize()
            #send first frame w tuple for tx_time and number of frames to put in slot
            blob = self.mgr.acquire(True)  #block
            more_frames = frame_count - 1
            msg = self.tx_queue.get()
            data = pmt.pmt_blob_data(msg.value)
            tx_object = time_object, data, more_frames
            self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('full'),
                          pmt.from_python(tx_object),
                          pmt.pmt_string_to_symbol('tdma'))
            frame_count -= 1

            old_data = []
            #print 'frame count: ',frame_count
            #send remining frames, blob only
            while (frame_count > 0):
                msg = self.tx_queue.get()
                data = pmt.pmt_blob_data(msg.value)
                blob = self.mgr.acquire(True)  #block
                pmt.pmt_blob_resize(blob, len(data))
                pmt.pmt_blob_rw_data(blob)[:] = data
                self.post_msg(TO_FRAMER_PORT,
                              pmt.pmt_string_to_symbol('d_only'), blob,
                              pmt.pmt_string_to_symbol('tdma'))
                frame_count -= 1
Beispiel #19
0
    def tx_frames(self):
        #send_sob
        #self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('tx_sob'), pmt.PMT_T, pmt.pmt_string_to_symbol('tx_sob'))

        #get all of the packets we want to send
        total_byte_count = 0
        frame_count = 0
        
        #put residue from previous execution
        if self.has_old_msg:
            length = len(pmt.pmt_blob_data(self.old_msg.value)) + self.overhead
            total_byte_count += length
            self.tx_queue.put(self.old_msg)
            frame_count += 1
            self.has_old_msg = False
            print 'old msg'

        #fill outgoing queue until empty or maximum bytes queued for slot
        while(not self.queue.empty()):
            msg = self.queue.get()
            length = len(pmt.pmt_blob_data(msg.value)) + self.overhead
            total_byte_count += length
            if total_byte_count >= self.bytes_per_slot:
                self.has_old_msg = True
                self.old_msg = msg
                print 'residue'
                continue
            else:
                self.has_old_msg = False
                self.tx_queue.put(msg)
                frame_count += 1
        
        time_object = int(math.floor(self.antenna_start)),(self.antenna_start % 1)
        
        #if no data, send a single pad frame
        #TODO: add useful pad data, i.e. current time of SDR
        if frame_count == 0:
            data = self.pad_data
            more_frames = 0
            tx_object = time_object,data,more_frames
            self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('full'),pmt.from_python(tx_object),pmt.pmt_string_to_symbol('tdma'))
        else:
            #print frame_count,self.queue.qsize(), self.tx_queue.qsize()
            #send first frame w tuple for tx_time and number of frames to put in slot
            blob = self.mgr.acquire(True) #block
            more_frames = frame_count - 1
            msg = self.tx_queue.get()
            data = pmt.pmt_blob_data(msg.value)
            tx_object = time_object,data,more_frames
            self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('full'),pmt.from_python(tx_object),pmt.pmt_string_to_symbol('tdma'))
            frame_count -= 1
            
            
            old_data = []
            #print 'frame count: ',frame_count
            #send remining frames, blob only
            while(frame_count > 0):
                msg = self.tx_queue.get()
                data = pmt.pmt_blob_data(msg.value)
                blob = self.mgr.acquire(True) #block
                pmt.pmt_blob_resize(blob, len(data))
                pmt.pmt_blob_rw_data(blob)[:] = data
                self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('d_only'),blob,pmt.pmt_string_to_symbol('tdma'))
                frame_count -= 1
Beispiel #20
0
    def tx_frames(self):
        #send_sob
        #self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('tx_sob'), pmt.PMT_T, pmt.pmt_string_to_symbol('tx_sob'))

        #get all of the packets we want to send
        total_byte_count = 0
        frame_count = 0

        #put residue from previous execution
        if self.has_old_msg:
            length = len(pmt.pmt_blob_data(self.old_msg.value)) + self.overhead
            total_byte_count += length
            self.tx_queue.put(self.old_msg)
            frame_count += 1
            self.has_old_msg = False
            print 'old msg'

        #fill outgoing queue until empty or maximum bytes queued for slot
        while (not self.queue.empty()):
            msg = self.queue.get()
            length = len(pmt.pmt_blob_data(msg.value)) + self.overhead
            total_byte_count += length
            if total_byte_count >= self.bytes_per_slot:
                self.has_old_msg = True
                self.old_msg = msg
                print 'residue'
                continue
            else:
                self.has_old_msg = False
                self.tx_queue.put(msg)
                frame_count += 1

        time_object = int(math.floor(
            self.antenna_start)), (self.antenna_start % 1)

        #if no data, send a single pad frame
        #TODO: add useful pad data, i.e. current time of SDR
        if frame_count == 0:
            #pad_d = struct.pack('!H', self.pktno & 0xffff) + (self.bytes_per_slot - 100) * chr(self.pktno & 0xff)
            #zeros = 64*chr(0x00)
            if self.initial_slot == 0:
                prefix = pn511s[0]
            else:
                prefix = pn511s[1]
            #for i in range(self.prefix_len):
            #    if i == self.prefix_loc:
            #        seg = zeros + pn511s[i]  #put the PN code to the prefix
            #    else:
            #        seg = 128*chr(0x00)
            # the prefix looks like  0000000...0000PPPPPP...PPPP0000000.....000000
            #                        |___512bit_||____512bit_||___M*1024bit_____|
            # M+N+1 := num_slots
            # N+1 := prefix_loc
            #    prefix = prefix + seg

            rdata = ''
            if self.from_file == 1 and self.sfile != 0:
                rdata = self.sfile.read(self.bytes_per_slot -
                                        64 * self.prefix_len - 100)
                if len(rdata) > 0:
                    pad_d = rdata
            elif self.from_file == 2 and self.sfile != 0:  #repeated sending the same packets for Virtual MIMO testing
                self.sfile.seek(0)  #go the beginning of file
                rdata = self.sfile.read(self.bytes_per_slot -
                                        64 * self.prefix_len - 100)
                if len(rdata) > 0:
                    pad_d = rdata
            else:
                if self.initial_slot == 0:  # use the unique PN code to specify the first slot
                    pad_d = 16 * pn511_0  #+ (self.bytes_per_slot - 64) * chr(self.pktno & 0xff)
                else:
                    pad_d = 16 * pn511_1

            pad_d = prefix + pad_d

            #send PN and data at different slots for MIMO
            postmsg = True
            if self.mimo == True:
                postmsg = True
                if self.pktno % 3 == self.prefix_loc:
                    pad_d = pn511_0
                elif self.pktno % 3 == 2:
                    pad_d = rdata
                else:
                    postmsg = False

            data = numpy.fromstring(pad_d, dtype='uint8')
            #data = self.pad_data
            #data = pad_d
            more_frames = 0
            tx_object = time_object, data, more_frames

            print 'prefix_loc = %d' % (self.prefix_loc)
            print 'antenna_start = %7f' % (self.antenna_start)

            if postmsg:
                self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('full'),
                              pmt.from_python(tx_object),
                              pmt.pmt_string_to_symbol('tdma'))
            self.pktno += 1
            #print 'tx_frames:post message from the pad data'
        else:
            #print frame_count,self.queue.qsize(), self.tx_queue.qsize()
            #send first frame w tuple for tx_time and number of frames to put in slot
            blob = self.mgr.acquire(True)  #block
            more_frames = frame_count - 1
            msg = self.tx_queue.get()
            data = pmt.pmt_blob_data(msg.value)
            tx_object = time_object, data, more_frames
            self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('full'),
                          pmt.from_python(tx_object),
                          pmt.pmt_string_to_symbol('tdma'))
            frame_count -= 1

            old_data = []
            #print 'frame count: ',frame_count
            #send remining frames, blob only
            while (frame_count > 0):
                msg = self.tx_queue.get()
                data = pmt.pmt_blob_data(msg.value)
                blob = self.mgr.acquire(True)  #block
                pmt.pmt_blob_resize(blob, len(data))
                pmt.pmt_blob_rw_data(blob)[:] = data
                self.post_msg(TO_FRAMER_PORT,
                              pmt.pmt_string_to_symbol('d_only'), blob,
                              pmt.pmt_string_to_symbol('tdma'))
                frame_count -= 1
Beispiel #21
0
 def send_pkt_radio(self,msg,pkt_cnt,dest,protocol_id,control):
     pkt_str = chr(pkt_cnt) + chr(self.addr) + chr(dest) + chr(protocol_id) + chr(control) + pmt.pmt_blob_data(msg.value).tostring()
     blob = self.mgr.acquire(True) #block
     pmt.pmt_blob_resize(blob, len(pkt_str))
     pmt.pmt_blob_rw_data(blob)[:] = numpy.fromstring(pkt_str, dtype='uint8')
     self.post_msg(0, pmt.pmt_string_to_symbol('U'), blob)
     return
Beispiel #22
0
    def work(self, input_items, output_items):
        while not len(self._pkt):
            try: msg = self.pop_msg_queue()
            except: return -1
            if not pmt.pmt_is_blob(msg.value): 
                self.tx_time,data,self.more_frame_cnt = pmt.to_python(msg.value)
                self.has_tx_time = True
                #print data
                #print tx_time
                #print data.tostring()
            else:
                data = pmt.pmt_blob_data(msg.value)
                #print data
                self.has_tx_time = False
            
                
            pkt = packet_utils.make_packet(
                data.tostring(),
                self._samples_per_symbol,
                self._bits_per_symbol,
                self._access_code,
                False, #pad_for_usrp,
                self._whitener_offset,
                )
            pkt += "".join(map(chr, [0x55] * 64))
            self._pkt = numpy.fromstring(pkt, numpy.uint8)
            if self._use_whitener_offset:
                self._whitener_offset = (self._whitener_offset + 1) % 16

            #shouldn't really need to send start of burst
            #only need to do sob if looking for timed transactions

            num_items = min(len(self._pkt), len(output_items[0]))
            output_items[0][:num_items] = self._pkt[:num_items]
            self._pkt = self._pkt[num_items:] #residue for next work()
            
            if len(self._pkt) == 0 :
                item_index = num_items #which output item gets the tag?
                offset = self.nitems_written(0) + item_index
                source = pmt.pmt_string_to_symbol("framer")
                
                #print 'frame cnt',self.more_frame_cnt
                
                if self.has_tx_time:
                    key = pmt.pmt_string_to_symbol("tx_sob")
                    self.add_item_tag(0, self.nitems_written(0), key, pmt.PMT_T, source)
                    key = pmt.pmt_string_to_symbol("tx_time")
                    self.add_item_tag(0, self.nitems_written(0), key, pmt.from_python(self.tx_time), source)
                    #if self.keep:
                    #    print 'bad order'
                    #self.keep = True

                
                if self.more_frame_cnt == 0:
                    key = pmt.pmt_string_to_symbol("tx_eob")
                    self.add_item_tag(0, offset - 1, key, pmt.PMT_T, source)
                    #if self.keep:
                    #    print 'good order'
                    #self.keep = False
                else:
                    self.more_frame_cnt -= 1

 
                
            return num_items
Beispiel #23
0
    def work(self, input_items, output_items):
        
        while(1):
            try: msg = self.pop_msg_queue()
            except: return -1
            
            if not pmt.pmt_is_blob(msg.value): 
                print self.addr
                print "not a blob - simple mac"
                continue

            self.key_string = pmt.pmt_symbol_to_string(msg.key)

            #receive data from application port to be transmitter to radio
            if msg.offset == APP_PORT:
                if(ord(self.key_string[KEY_INDEX_CTRL]) == ARQ_REQ):
                    self.queue.put(msg)
                if(ord(self.key_string[KEY_INDEX_CTRL]) == ARQ_NO_REQ):
                    self.tx_no_arq(msg,ord(self.key_string[KEY_INDEX_DEST_ADDR]),USER_IO_PROTOCOL_ID)        
            
            #TODO: Oh my goodness, this section is ugly. I need to clean this.
            #process the packet    received on radio    
            if(msg.offset == RADIO_PORT):
                incoming_pkt = pmt.pmt_blob_data(msg.value)    #get data
                if ( len(incoming_pkt) > 5 ): #check for weird header only stuff
                    if( ( incoming_pkt[PKT_INDEX_DEST] == self.addr or incoming_pkt[PKT_INDEX_DEST] == 255)  and not incoming_pkt[PKT_INDEX_SRC] == self.addr):    #for us?         
                        #check to see if we must ACK this packet
                        if(incoming_pkt[PKT_INDEX_CTRL] == ARQ_REQ): #TODO, stuff CTRL and Protocol in one field
                            self.send_ack(incoming_pkt,incoming_pkt[PKT_INDEX_SRC],incoming_pkt[PKT_INDEX_CNT])                        #Then send ACK then
                            if not (self.arq_expected_sequence_number == incoming_pkt[PKT_INDEX_CNT]):
                                self.arq_sequence_error_cnt += 1
                                self.throw_away = True
                            else:
                                self.throw_away = False
                            self.arq_expected_sequence_number =  ( incoming_pkt[PKT_INDEX_CNT] + 1 ) % 255 
                        else:
                            if not (self.no_arq_expected_sequence_number == incoming_pkt[PKT_INDEX_CNT]):
                                self.no_arq_sequence_error_cnt += 1
                                #print self.no_arq_sequence_error_cnt
                                #print self.no_arq_sequence_error_cnt,incoming_pkt[PKT_INDEX_CNT],self.no_arq_expected_sequence_number
                            self.no_arq_expected_sequence_number =  ( incoming_pkt[PKT_INDEX_CNT] + 1 ) % 255 

                        incoming_protocol_id = incoming_pkt[PKT_INDEX_PROT_ID]
                        
                        #check to see if this is an ACK packet
                        if(incoming_protocol_id == ARQ_PROTOCOL_ID):
                            if incoming_pkt[5] == self.expected_arq_id:
                                self.arq_channel_state = ARQ_CHANNEL_IDLE
                                self.pkt_cnt_arq = ( self.pkt_cnt_arq + 1 ) % 255
                            else:
                                print 'received out of sequence ack',incoming_pkt[5],self.expected_arq_id
                        
                        #do something with incoming user data
                        elif(incoming_protocol_id == USER_IO_PROTOCOL_ID):
                            if not self.throw_away:
                                self.output_user_data(incoming_pkt)   
                            self.throw_away = False
                                
                        else:
                            print 'unknown protocol'

            if(msg.offset == CTRL_PORT):
                if(self.key_string[KEY_INT_MSG_TYPE] == HEARTBEAT):
                        #TODO: something useful when we receive heartbeat?
                        a = '0'
                
                        
                                    
            #check to see if we have any outgoing messages from arq buffer we should send
            #or pending re-transmissions
            if self.arq_channel_state == ARQ_CHANNEL_IDLE: #channel ready for next arq msg
                if not self.queue.empty(): #we have an arq msg to send, so lets send it
                    #print self.queue.qsize()
                    self.outgoing_msg = self.queue.get() #get msg
                    self.expected_arq_id = self.pkt_cnt_arq #store it for re-use
                    self.key_string = pmt.pmt_symbol_to_string(self.outgoing_msg.key) #pull key
                    self.tx_arq(self.outgoing_msg,ord(self.key_string[KEY_INDEX_DEST_ADDR]),USER_IO_PROTOCOL_ID) #transmit it
                    self.time_of_tx = time.time() # note time for arq timeout recognition
                    self.arq_channel_state = ARQ_CHANNEL_BUSY #remember that the channel is busy
                    self.arq_pkts_txed += 1
                    self.retries = 0
            else: #if channel is busy, lets check to see if its time to re-transmit
                if ( time.time() - self.time_of_tx ) > self.timeout: #check for ack timeout
                    if self.retries == self.max_attempts:            #know when to quit
                        self.retries = 0 
                        self.arq_channel_state = ARQ_CHANNEL_IDLE
                        self.failed_arq += 1
                        self.pkt_cnt_arq = ( self.pkt_cnt_arq + 1 ) % 255   #start on next pkt
                        print 'pkt failed arq'
                    else:    
                        self.key_string = pmt.pmt_symbol_to_string(self.outgoing_msg.key) #reset key
                        self.tx_arq(self.outgoing_msg,ord(self.key_string[KEY_INDEX_DEST_ADDR]),USER_IO_PROTOCOL_ID) #tx again
                        self.time_of_tx = time.time()
                        self.arq_retxed += 1
                        self.retries += 1
Beispiel #24
0
    def work(self, input_items, output_items):
        while not len(self._pkt):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1
            if not pmt.pmt_is_blob(msg.value):
                self.tx_time, data, self.more_frame_cnt = pmt.to_python(
                    msg.value)
                self.has_tx_time = True
                #print data
                #print tx_time
                #print data.tostring()
            else:
                data = pmt.pmt_blob_data(msg.value)
                #print data
                self.has_tx_time = False

            pkt = packet_utils.make_packet(
                data.tostring(),
                self._samples_per_symbol,
                self._bits_per_symbol,
                self._access_code,
                False,  #pad_for_usrp,
                self._whitener_offset,
            )
            self._pkt = numpy.fromstring(pkt, numpy.uint8)
            if self._use_whitener_offset:
                self._whitener_offset = (self._whitener_offset + 1) % 16

            #shouldn't really need to send start of burst
            #only need to do sob if looking for timed transactions

            num_items = min(len(self._pkt), len(output_items[0]))
            output_items[0][:num_items] = self._pkt[:num_items]
            self._pkt = self._pkt[num_items:]  #residue for next work()

            if len(self._pkt) == 0:
                item_index = num_items  #which output item gets the tag?
                offset = self.nitems_written(0) + item_index
                source = pmt.pmt_string_to_symbol("framer")

                #print 'frame cnt',self.more_frame_cnt

                if self.has_tx_time:
                    key = pmt.pmt_string_to_symbol("tx_sob")
                    self.add_item_tag(0, self.nitems_written(0), key,
                                      pmt.PMT_T, source)
                    key = pmt.pmt_string_to_symbol("tx_time")
                    self.add_item_tag(0, self.nitems_written(0), key,
                                      pmt.from_python(self.tx_time), source)
                    #if self.keep:
                    #    print 'bad order'
                    #self.keep = True

                if self.more_frame_cnt == 0:
                    key = pmt.pmt_string_to_symbol("tx_eob")
                    self.add_item_tag(0, offset - 1, key, pmt.PMT_T, source)
                    #if self.keep:
                    #    print 'good order'
                    #self.keep = False
                else:
                    self.more_frame_cnt -= 1

            return num_items
Beispiel #25
0
    def tx_frames(self):
        #send_sob
        #self.post_msg(TO_FRAMER_PORT, pmt.pmt_string_to_symbol('tx_sob'), pmt.PMT_T, pmt.pmt_string_to_symbol('tx_sob'))

        #get all of the packets we want to send
        total_byte_count = 0
        frame_count = 0
        
        #put residue from previous execution
        if self.has_old_msg:
            length = len(pmt.pmt_blob_data(self.old_msg.value)) + self.overhead
            total_byte_count += length
            self.tx_queue.put(self.old_msg)
            frame_count += 1
            self.has_old_msg = False
            print 'old msg'

        #fill outgoing queue until empty or maximum bytes queued for slot
        while(not self.queue.empty()):
            msg = self.queue.get()
            length = len(pmt.pmt_blob_data(msg.value)) + self.overhead
            total_byte_count += length
            if total_byte_count >= self.bytes_per_slot:
                self.has_old_msg = True
                self.old_msg = msg
                print 'residue'
                continue
            else:
                self.has_old_msg = False
                self.tx_queue.put(msg)
                frame_count += 1
        
        time_object = int(math.floor(self.antenna_start)),(self.antenna_start % 1)
        
        #if no data, send a single pad frame
        #TODO: add useful pad data, i.e. current time of SDR
        if frame_count == 0:
            #pad_d = struct.pack('!H', self.pktno & 0xffff) + (self.bytes_per_slot - 100) * chr(self.pktno & 0xff)
            #zeros = 64*chr(0x00)
            if self.initial_slot == 0:
                prefix = pn511s[0]
            else:
                prefix = pn511s[1]
            #for i in range(self.prefix_len):
            #    if i == self.prefix_loc:
            #        seg = zeros + pn511s[i]  #put the PN code to the prefix
            #    else:
            #        seg = 128*chr(0x00)
                # the prefix looks like  0000000...0000PPPPPP...PPPP0000000.....000000
                #                        |___512bit_||____512bit_||___M*1024bit_____|
                # M+N+1 := num_slots
                # N+1 := prefix_loc
            #    prefix = prefix + seg

            rdata = ''
            if self.from_file == 1 and self.sfile != 0:
                rdata = self.sfile.read(self.bytes_per_slot - 64*self.prefix_len -100)
                if len(rdata) > 0:
                    pad_d = rdata
            elif self.from_file == 2 and self.sfile != 0: #repeated sending the same packets for Virtual MIMO testing
 		self.sfile.seek(0) #go the beginning of file
		rdata = self.sfile.read(self.bytes_per_slot - 64*self.prefix_len -100)
		if len(rdata) > 0:
                    pad_d = rdata
            else:
                if self.initial_slot == 0: # use the unique PN code to specify the first slot
                    pad_d = 16*pn511_0 #+ (self.bytes_per_slot - 64) * chr(self.pktno & 0xff)
                else:
                    pad_d = 16*pn511_1
                
            pad_d = prefix + pad_d
 
            #send PN and data at different slots for MIMO
            postmsg = True
            if self.mimo == True:       
                postmsg = True
                if self.pktno % 3 == self.prefix_loc:
                    pad_d = pn511_0
                elif self.pktno % 3 == 2:
                    pad_d = rdata
                else:
                    postmsg = False
                

            data  = numpy.fromstring(pad_d, dtype='uint8')
            #data = self.pad_data
            #data = pad_d
            more_frames = 0
            tx_object = time_object,data,more_frames

            print 'prefix_loc = %d' %(self.prefix_loc)
            print 'antenna_start = %7f' %(self.antenna_start)
            
            if postmsg:
                self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('full'),pmt.from_python(tx_object),pmt.pmt_string_to_symbol('tdma'))
            self.pktno += 1
            #print 'tx_frames:post message from the pad data'
        else:
            #print frame_count,self.queue.qsize(), self.tx_queue.qsize()
            #send first frame w tuple for tx_time and number of frames to put in slot
            blob = self.mgr.acquire(True) #block
            more_frames = frame_count - 1
            msg = self.tx_queue.get()
            data = pmt.pmt_blob_data(msg.value)
            tx_object = time_object,data,more_frames
            self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('full'),pmt.from_python(tx_object),pmt.pmt_string_to_symbol('tdma'))
            frame_count -= 1
            
            
            old_data = []
            #print 'frame count: ',frame_count
            #send remining frames, blob only
            while(frame_count > 0):
                msg = self.tx_queue.get()
                data = pmt.pmt_blob_data(msg.value)
                blob = self.mgr.acquire(True) #block
                pmt.pmt_blob_resize(blob, len(data))
                pmt.pmt_blob_rw_data(blob)[:] = data
                self.post_msg(TO_FRAMER_PORT,pmt.pmt_string_to_symbol('d_only'),blob,pmt.pmt_string_to_symbol('tdma'))
                frame_count -= 1
Beispiel #26
0
    def work(self, input_items, output_items):

        while (1):
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if not pmt.pmt_is_blob(msg.value):
                print self.addr
                print "not a blob - simple mac"
                continue

            self.key_string = pmt.pmt_symbol_to_string(msg.key)

            #receive data from application port to be transmitter to radio
            if msg.offset == APP_PORT:
                if (ord(self.key_string[KEY_INDEX_CTRL]) == ARQ_REQ):
                    self.queue.put(msg)
                if (ord(self.key_string[KEY_INDEX_CTRL]) == ARQ_NO_REQ):
                    self.tx_no_arq(msg,
                                   ord(self.key_string[KEY_INDEX_DEST_ADDR]),
                                   USER_IO_PROTOCOL_ID)

            #TODO: Oh my goodness, this section is ugly. I need to clean this.
            #process the packet    received on radio
            if (msg.offset == RADIO_PORT):
                incoming_pkt = pmt.pmt_blob_data(msg.value)  #get data
                if (len(incoming_pkt) > 5):  #check for weird header only stuff
                    if ((incoming_pkt[PKT_INDEX_DEST] == self.addr
                         or incoming_pkt[PKT_INDEX_DEST] == 255)
                            and not incoming_pkt[PKT_INDEX_SRC]
                            == self.addr):  #for us?
                        #check to see if we must ACK this packet
                        if (incoming_pkt[PKT_INDEX_CTRL] == ARQ_REQ
                            ):  #TODO, stuff CTRL and Protocol in one field
                            self.send_ack(incoming_pkt,
                                          incoming_pkt[PKT_INDEX_SRC],
                                          incoming_pkt[PKT_INDEX_CNT]
                                          )  #Then send ACK then
                            if not (self.arq_expected_sequence_number
                                    == incoming_pkt[PKT_INDEX_CNT]):
                                self.arq_sequence_error_cnt += 1
                                self.throw_away = True
                            else:
                                self.throw_away = False
                            self.arq_expected_sequence_number = (
                                incoming_pkt[PKT_INDEX_CNT] + 1) % 255
                        else:
                            if not (self.no_arq_expected_sequence_number
                                    == incoming_pkt[PKT_INDEX_CNT]):
                                self.no_arq_sequence_error_cnt += 1
                                #print self.no_arq_sequence_error_cnt
                                #print self.no_arq_sequence_error_cnt,incoming_pkt[PKT_INDEX_CNT],self.no_arq_expected_sequence_number
                            self.no_arq_expected_sequence_number = (
                                incoming_pkt[PKT_INDEX_CNT] + 1) % 255

                        incoming_protocol_id = incoming_pkt[PKT_INDEX_PROT_ID]

                        #check to see if this is an ACK packet
                        if (incoming_protocol_id == ARQ_PROTOCOL_ID):
                            if incoming_pkt[5] == self.expected_arq_id:
                                self.arq_channel_state = ARQ_CHANNEL_IDLE
                                self.pkt_cnt_arq = (self.pkt_cnt_arq + 1) % 255
                            else:
                                print 'received out of sequence ack', incoming_pkt[
                                    5], self.expected_arq_id

                        #do something with incoming user data
                        elif (incoming_protocol_id == USER_IO_PROTOCOL_ID):
                            if not self.throw_away:
                                self.output_user_data(incoming_pkt)
                            self.throw_away = False

                        else:
                            print 'unknown protocol'

            if (msg.offset == CTRL_PORT):
                if (self.key_string[KEY_INT_MSG_TYPE] == HEARTBEAT):
                    #TODO: something useful when we receive heartbeat?
                    a = '0'

            #check to see if we have any outgoing messages from arq buffer we should send
            #or pending re-transmissions
            if self.arq_channel_state == ARQ_CHANNEL_IDLE:  #channel ready for next arq msg
                if not self.queue.empty(
                ):  #we have an arq msg to send, so lets send it
                    #print self.queue.qsize()
                    self.outgoing_msg = self.queue.get()  #get msg
                    self.expected_arq_id = self.pkt_cnt_arq  #store it for re-use
                    self.key_string = pmt.pmt_symbol_to_string(
                        self.outgoing_msg.key)  #pull key
                    self.tx_arq(self.outgoing_msg,
                                ord(self.key_string[KEY_INDEX_DEST_ADDR]),
                                USER_IO_PROTOCOL_ID)  #transmit it
                    self.time_of_tx = time.time(
                    )  # note time for arq timeout recognition
                    self.arq_channel_state = ARQ_CHANNEL_BUSY  #remember that the channel is busy
                    self.arq_pkts_txed += 1
                    self.retries = 0
            else:  #if channel is busy, lets check to see if its time to re-transmit
                if (time.time() - self.time_of_tx
                    ) > self.timeout:  #check for ack timeout
                    if self.retries == self.max_attempts:  #know when to quit
                        self.retries = 0
                        self.arq_channel_state = ARQ_CHANNEL_IDLE
                        self.failed_arq += 1
                        self.pkt_cnt_arq = (self.pkt_cnt_arq +
                                            1) % 255  #start on next pkt
                        print 'pkt failed arq'
                    else:
                        self.key_string = pmt.pmt_symbol_to_string(
                            self.outgoing_msg.key)  #reset key
                        self.tx_arq(self.outgoing_msg,
                                    ord(self.key_string[KEY_INDEX_DEST_ADDR]),
                                    USER_IO_PROTOCOL_ID)  #tx again
                        self.time_of_tx = time.time()
                        self.arq_retxed += 1
                        self.retries += 1
Beispiel #27
0
    def work(self, input_items, output_items):

        if self.rx_state == RX_INIT:
            self.rx_hop_index = 0
            self.rx_state = RX_SEARCH
            self.post_msg(
                CTRL_PORT,
                pmt.pmt_string_to_symbol('usrp_source.set_center_freq'),
                pmt.from_python(
                    ((self.rx_freq_list[self.rx_hop_index], ), {})),
                pmt.pmt_string_to_symbol('fhss'))
            self.rx_hop_index = (self.rx_hop_index +
                                 1) % self.rx_freq_list_length
            print 'Initialized to channel 0.  Searching...'

        #check for msg inputs when work function is called
        if self.check_msg_queue():
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if msg.offset == INCOMING_PKT_PORT:
                pkt = pmt.pmt_blob_data(msg.value)
                if pkt[0]:
                    blob = self.mgr.acquire(True)  #block
                    pmt.pmt_blob_resize(blob, len(pkt) - 1)
                    pmt.pmt_blob_rw_data(blob)[:] = pkt[1:]
                    self.post_msg(APP_PORT, pmt.pmt_string_to_symbol('rx'),
                                  blob, pmt.pmt_string_to_symbol('fhss'))
                if self.know_time:
                    if self.rx_state == RX_SEARCH:
                        self.rx_state = RX_FOUND
                        self.pkt_received = True
                        self.next_tune_time = self.time_update + self.hop_interval - self.tune_lead
                        self.start_hop = self.next_tune_time - self.lead_limit
                        print 'Received packet.  Locked.  Hopping initialized.'
                    else:
                        self.pkt_received = True
                        #print 'pkt_rcved_2',self.time_update,self.start_hop,self.next_tune_time

            else:
                a = 0  #CONTROL port

        #process streaming samples and tags here
        in0 = input_items[0]
        nread = self.nitems_read(0)  #number of items read on port 0
        ninput_items = len(input_items[0])

        #read all tags associated with port 0 for items in this work function
        tags = self.get_tags_in_range(0, nread, nread + ninput_items)

        #lets find all of our tags, making the appropriate adjustments to our timing
        for tag in tags:
            key_string = pmt.pmt_symbol_to_string(tag.key)
            if key_string == "rx_time":
                self.samples_since_last_rx_time = 0
                self.current_integer, self.current_fractional = pmt.to_python(
                    tag.value)
                self.time_update = self.current_integer + self.current_fractional
                self.found_time = True
            elif key_string == "rx_rate":
                self.rate = pmt.to_python(tag.value)
                self.sample_period = 1 / self.rate
                self.found_rate = True

        #determine first transmit slot when we learn the time
        if not self.know_time:
            if self.found_time and self.found_rate:
                self.know_time = True
        else:
            #get current time
            self.time_update += (self.sample_period * ninput_items)

        if self.rx_state == RX_FOUND:
            if self.time_update > self.start_hop:
                #print 'set: ', self.rx_freq_list[self.rx_hop_index], self.time_update, self.next_tune_time
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol('usrp_source.set_command_time'),
                    pmt.from_python(((self.next_tune_time, ), {})),
                    pmt.pmt_string_to_symbol('fhss'))
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol('usrp_source.set_center_freq'),
                    pmt.from_python(
                        ((self.rx_freq_list[self.rx_hop_index], ), {})),
                    pmt.pmt_string_to_symbol('fhss'))
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol('usrp_source.clear_command_time'),
                    pmt.from_python(((0, ), {})),
                    pmt.pmt_string_to_symbol('fhss'))
                self.rx_hop_index = (self.rx_hop_index +
                                     1) % self.rx_freq_list_length
                self.start_hop += self.hop_interval
                self.next_tune_time += self.hop_interval
                #self.next_rx_interval += self.hop_interval - self.tune_lead
                if self.pkt_received:
                    self.consecutive_miss = 0
                else:
                    self.consecutive_miss += 1

                if self.consecutive_miss > LOST_SYNC_THRESHOLD:
                    self.consecutive_miss = 0
                    self.rx_state = RX_INIT
                    print 'Lost Sync: Re-Initializing'

                self.pkt_received = False

        return ninput_items
Beispiel #28
0
    def work(self, input_items, output_items):

        if self.rx_state == RX_INIT:
            self.rx_hop_index = 0
            self.rx_state = RX_SEARCH
            self.post_msg(
                CTRL_PORT,
                pmt.pmt_string_to_symbol("usrp_source.set_center_freq"),
                pmt.from_python(((self.rx_freq_list[self.rx_hop_index],), {})),
                pmt.pmt_string_to_symbol("fhss"),
            )
            self.rx_hop_index = (self.rx_hop_index + 1) % self.rx_freq_list_length
            print "Initialized to channel 0.  Searching..."

        # check for msg inputs when work function is called
        if self.check_msg_queue():
            try:
                msg = self.pop_msg_queue()
            except:
                return -1

            if msg.offset == INCOMING_PKT_PORT:
                pkt = pmt.pmt_blob_data(msg.value)
                if pkt[0]:
                    blob = self.mgr.acquire(True)  # block
                    pmt.pmt_blob_resize(blob, len(pkt) - 1)
                    pmt.pmt_blob_rw_data(blob)[:] = pkt[1:]
                    self.post_msg(APP_PORT, pmt.pmt_string_to_symbol("rx"), blob, pmt.pmt_string_to_symbol("fhss"))
                if self.know_time:
                    if self.rx_state == RX_SEARCH:
                        self.rx_state = RX_FOUND
                        self.pkt_received = True
                        self.next_tune_time = self.time_update + self.hop_interval - self.tune_lead
                        self.start_hop = self.next_tune_time - self.lead_limit
                        print "Received packet.  Locked.  Hopping initialized."
                    else:
                        self.pkt_received = True
                        # print 'pkt_rcved_2',self.time_update,self.start_hop,self.next_tune_time

            else:
                a = 0  # CONTROL port

        # process streaming samples and tags here
        in0 = input_items[0]
        nread = self.nitems_read(0)  # number of items read on port 0
        ninput_items = len(input_items[0])

        # read all tags associated with port 0 for items in this work function
        tags = self.get_tags_in_range(0, nread, nread + ninput_items)

        # lets find all of our tags, making the appropriate adjustments to our timing
        for tag in tags:
            key_string = pmt.pmt_symbol_to_string(tag.key)
            if key_string == "rx_time":
                self.samples_since_last_rx_time = 0
                self.current_integer, self.current_fractional = pmt.to_python(tag.value)
                self.time_update = self.current_integer + self.current_fractional
                self.found_time = True
            elif key_string == "rx_rate":
                self.rate = pmt.to_python(tag.value)
                self.sample_period = 1 / self.rate
                self.found_rate = True

        # determine first transmit slot when we learn the time
        if not self.know_time:
            if self.found_time and self.found_rate:
                self.know_time = True
        else:
            # get current time
            self.time_update += self.sample_period * ninput_items

        if self.rx_state == RX_FOUND:
            if self.time_update > self.start_hop:
                # print 'set: ', self.rx_freq_list[self.rx_hop_index], self.time_update, self.next_tune_time
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol("usrp_source.set_command_time"),
                    pmt.from_python(((self.next_tune_time,), {})),
                    pmt.pmt_string_to_symbol("fhss"),
                )
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol("usrp_source.set_center_freq"),
                    pmt.from_python(((self.rx_freq_list[self.rx_hop_index],), {})),
                    pmt.pmt_string_to_symbol("fhss"),
                )
                self.post_msg(
                    CTRL_PORT,
                    pmt.pmt_string_to_symbol("usrp_source.clear_command_time"),
                    pmt.from_python(((0,), {})),
                    pmt.pmt_string_to_symbol("fhss"),
                )
                self.rx_hop_index = (self.rx_hop_index + 1) % self.rx_freq_list_length
                self.start_hop += self.hop_interval
                self.next_tune_time += self.hop_interval
                # self.next_rx_interval += self.hop_interval - self.tune_lead
                if self.pkt_received:
                    self.consecutive_miss = 0
                else:
                    self.consecutive_miss += 1

                if self.consecutive_miss > LOST_SYNC_THRESHOLD:
                    self.consecutive_miss = 0
                    self.rx_state = RX_INIT
                    print "Lost Sync: Re-Initializing"

                self.pkt_received = False

        return ninput_items