def __init__(self, options, msgq_limit=2, pad_for_usrp=True):
"""
Hierarchical block for sending packets
Packets to be sent are enqueued by calling send_pkt.
The output is the complex modulated signal at baseband.
@param options: pass modulation options from higher layers (fft length, occupied tones, etc.)
@param msgq_limit: maximum number of messages in message queue
@type msgq_limit: int
@param pad_for_usrp: If true, packets are padded such that they end up a multiple of 128 samples
"""
gr.hier_block2.__init__(
self,
"ofdm_mod",
gr.io_signature(0, 0, 0), # Input signature
gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
self._pad_for_usrp = pad_for_usrp
self._modulation = options.modulation
self._fft_length = options.fft_length
self._occupied_tones = options.occupied_tones
self._cp_length = options.cp_length
win = [] #[1 for i in range(self._fft_length)]
# Use freq domain to get doubled-up known symbol for correlation in time domain
zeros_on_left = int(
math.ceil((self._fft_length - self._occupied_tones) / 2.0))
ksfreq = known_symbols_4512_3[0:self._occupied_tones]
for i in range(len(ksfreq)):
if ((zeros_on_left + i) & 1):
ksfreq[i] = 0
# hard-coded known symbols
preambles = (ksfreq, )
padded_preambles = list()
for pre in preambles:
padded = self._fft_length * [
0,
]
padded[zeros_on_left:zeros_on_left + self._occupied_tones] = pre
padded_preambles.append(padded)
symbol_length = options.fft_length + options.cp_length
mods = {
"bpsk": 2,
"qpsk": 4,
"8psk": 8,
"qam8": 8,
"qam16": 16,
"qam64": 64,
"qam256": 256
}
arity = mods[self._modulation]
rot = 1
if self._modulation == "qpsk":
rot = (0.707 + 0.707j)
if (self._modulation.find("psk") >= 0):
rotated_const = map(lambda pt: pt * rot,
psk.gray_constellation[arity])
elif (self._modulation.find("qam") >= 0):
rotated_const = map(lambda pt: pt * rot, qam.constellation[arity])
#print rotated_const
self._pkt_input = gr.ofdm_mapper_bcv(rotated_const, msgq_limit,
options.occupied_tones,
options.fft_length)
self.preambles = gr.ofdm_insert_preamble(self._fft_length,
padded_preambles)
self.ifft = gr.fft_vcc(self._fft_length, False, win, True)
self.cp_adder = gr.ofdm_cyclic_prefixer(self._fft_length,
symbol_length)
self.scale = gr.multiply_const_cc(1.0 / math.sqrt(self._fft_length))
self.connect((self._pkt_input, 0), (self.preambles, 0))
self.connect((self._pkt_input, 1), (self.preambles, 1))
self.connect(self.preambles, self.ifft, self.cp_adder, self.scale,
self)
if options.verbose:
self._print_verbage()
if options.log:
self.connect(
self._pkt_input,
gr.file_sink(gr.sizeof_gr_complex * options.fft_length,
"ofdm_mapper_c.dat"))
self.connect(
self.preambles,
gr.file_sink(gr.sizeof_gr_complex * options.fft_length,
"ofdm_preambles.dat"))
self.connect(
self.ifft,
gr.file_sink(gr.sizeof_gr_complex * options.fft_length,
"ofdm_ifft_c.dat"))
self.connect(
self.cp_adder,
gr.file_sink(gr.sizeof_gr_complex, "ofdm_cp_adder_c.dat"))
def __init__(self, options, msgq_limit=2, pad_for_usrp=True):
"""
Hierarchical block for sending packets
Packets to be sent are enqueued by calling send_pkt.
The output is the complex modulated signal at baseband.
@param options: pass modulation options from higher layers (fft length, occupied tones, etc.)
@param msgq_limit: maximum number of messages in message queue
@type msgq_limit: int
@param pad_for_usrp: If true, packets are padded such that they end up a multiple of 128 samples
"""
gr.hier_block2.__init__(self, "ofdm_mod",
gr.io_signature(0, 0, 0), # Input signature
gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
self._pad_for_usrp = pad_for_usrp
self._modulation = options.modulation
self._fft_length = options.fft_length
self._occupied_tones = options.occupied_tones
self._cp_length = options.cp_length
win = [] #[1 for i in range(self._fft_length)]
# Use freq domain to get doubled-up known symbol for correlation in time domain
zeros_on_left = int(math.ceil((self._fft_length - self._occupied_tones)/2.0))
ksfreq = known_symbols_4512_3[0:self._occupied_tones]
for i in range(len(ksfreq)):
if((zeros_on_left + i) & 1):
ksfreq[i] = 0
# hard-coded known symbols
preambles = (ksfreq,)
padded_preambles = list()
for pre in preambles:
padded = self._fft_length*[0,]
padded[zeros_on_left : zeros_on_left + self._occupied_tones] = pre
padded_preambles.append(padded)
symbol_length = options.fft_length + options.cp_length
mods = {"bpsk": 2, "qpsk": 4, "8psk": 8, "qam8": 8, "qam16": 16, "qam64": 64, "qam256": 256}
arity = mods[self._modulation]
rot = 1
if self._modulation == "qpsk":
rot = (0.707+0.707j)
if(self._modulation.find("psk") >= 0):
rotated_const = map(lambda pt: pt * rot, psk.gray_constellation[arity])
elif(self._modulation.find("qam") >= 0):
rotated_const = map(lambda pt: pt * rot, qam.constellation[arity])
#print rotated_const
self._pkt_input = gr.ofdm_mapper_bcv(rotated_const, msgq_limit,
options.occupied_tones, options.fft_length)
self.preambles = gr.ofdm_insert_preamble(self._fft_length, padded_preambles)
self.ifft = gr.fft_vcc(self._fft_length, False, win, True)
self.cp_adder = gr.ofdm_cyclic_prefixer(self._fft_length, symbol_length)
self.scale = gr.multiply_const_cc(1.0 / math.sqrt(self._fft_length))
self.connect((self._pkt_input, 0), (self.preambles, 0))
self.connect((self._pkt_input, 1), (self.preambles, 1))
self.connect(self.preambles, self.ifft, self.cp_adder, self.scale, self)
if options.verbose:
self._print_verbage()
if options.log:
self.connect(self._pkt_input, gr.file_sink(gr.sizeof_gr_complex*options.fft_length,
"ofdm_mapper_c.dat"))
self.connect(self.preambles, gr.file_sink(gr.sizeof_gr_complex*options.fft_length,
"ofdm_preambles.dat"))
self.connect(self.ifft, gr.file_sink(gr.sizeof_gr_complex*options.fft_length,
"ofdm_ifft_c.dat"))
self.connect(self.cp_adder, gr.file_sink(gr.sizeof_gr_complex,
"ofdm_cp_adder_c.dat"))
def __init__(self):
parser = OptionParser(option_class=eng_option, conflict_handler="resolve")
expert_grp = parser.add_option_group("Expert")
parser.add_option("-s", "--size", type="eng_float", default=400,
help="set packet size [default=%default]")
parser.add_option("-M", "--megabytes", type="eng_float", default=1.0,
help="set megabytes to transmit [default=%default]")
parser.add_option("","--discontinuous", action="store_true", default=False,
help="enable discontinuous mode")
(options, args) = parser.parse_args ()
msgq_limit=2
gr.top_block.__init__(self)
padded_preambles = list()
# Set of pre-defined parameters. In actual code this is passed as parameter in options
#known_symb = [-1, -1, 1, -1, 1, 1, -1, -1, 1, -1, 1, 1, -1, 1, -1, -1]
known_symb = 1000 *[1,-1]
fft_length = 512
occupied_tones = 200
cp_length = 128
pad_for_usrp = True
modulation = "qpsk"
zeros_on_left= int(math.ceil((fft_length - occupied_tones)/2.0))
ksfreq = known_symb[0:occupied_tones]
preambles = (ksfreq,)
print zeros_on_left
for pre in preambles:
padded = fft_length*[0,]
padded[zeros_on_left : zeros_on_left + occupied_tones] = pre
padded_preambles.append(padded)
symbol_length = fft_length + cp_length
#mods returns the number of points in the constellation given the index as the mod type "bpsk" etc
mods = {"bpsk": 2, "qpsk": 4, "8psk": 8, "qam8": 8, "qam16": 16, "qam64": 64, "qam256": 256}
arity = mods[modulation]
rot = 1
if modulation == "qpsk":
rot = (0.707+0.707j)
if(modulation.find("psk") >= 0):#check if it is psk or qpsk, returns the position of string "psk"
rotated_const = map(lambda pt: pt * rot, psk.gray_constellation[arity])
elif(modulation.find("qam") >= 0):
rotated_const = map(lambda pt: pt * rot, qam.constellation[arity])
#print rotated_const
self._pkt_input = gr.ofdm_mapper_bcv(rotated_const, msgq_limit,
occupied_tones,fft_length)
self.preambles_2 = gr.ofdm_insert_preamble(fft_length,padded_preambles)
#Setting up the user defined data to test the working of the blocks
data1 = 512*[complex(2,3)] #How to generate complex modulated values
twos = 511*[1]
twos_arr = array('B',twos)
data2 = array('B',[1])
data2.extend(twos_arr)
#print data
self.data_src1 = gr.vector_source_c(data1,True,16)
self.data_src2 = gr.vector_source_b(data2,True,1)
self.sink_n = gr.vector_sink_c(512)
# End of data setting
self.sink_file = gr.file_sink(512*gr.sizeof_gr_complex,'pad')
v2s = gr.vector_to_stream(4096,1)
self.connect((self._pkt_input,0),(self.preambles_2,0))
self.connect((self._pkt_input,1),(self.preambles_2,1))
self.connect((self.preambles_2,0),self.sink_n)
self.connect((self.preambles_2,0),self.sink_file)
