def rcos_bpsk_map(t, data, b_rate, **args):
"""
Generates a baseband signal to modulate with BPSK and raised cosine pulses
:param t: time axis
:param data: binary sequence which is going to be mapped
:param b_rate: bit rate of the transmitted bit-stream
:param args: optional arguments, see the table.
+----------+-------------+-----------+---------------------------------------------------+
| Key word | Possible | Default | Description |
| | values | | |
+==========+=============+===========+===================================================+
| tp | positive | | pulse width of a single symbol |
| | float | 1/b_rate | |
+----------+-------------+-----------+---------------------------------------------------+
| td | positive | | delay of the signal with reference to the origin |
| | float | 0 | of the time axis |
+----------+-------------+-----------+---------------------------------------------------+
| pw | positive | 1/b_rate | pulse width of the sinc - main lobe |
| | float | | |
+----------+-------------+-----------+---------------------------------------------------+
| alpha | positive | 0.8 | roll-off factor |
| | float | | |
+----------+-------------+-----------+---------------------------------------------------+
:return: Baseband signal
"""
if 'tp' in args:
tp = args['tp']
else:
tp = 1 / b_rate # pulse width of a single symbol
if 'td' in args:
td = args['td']
else:
td = 0 # signal starts at time td = 0s
if 'pw' in args:
pw = args['pw']
else:
pw = 1 / b_rate # pulse width of the sinc - main lobe
if 'alpha' in args:
alpha = args['alpha']
else:
alpha = .8 # roll-off factor
# Baseband signal generator
i_bb = 2 * gen.rcos_tr(t, tp, td, data, pw, alpha) - 1
q_bb = np.zeros(np.size(t))
bb = i_bb + q_bb * 1j
return (bb)
f_sampl = 50e3 # sampling frequency in kHz T_int = 1.8 # entire signal length in ms ##################### Simulation TAU = 1 ###################### t = np.arange(0,T_int,1/f_sampl) # time axis f = ut.freq_fr_time (t) # frequency axis tc = ut.corr_fr_time (t) # correlation time axis cd = np.array([1,1,1,0,1,1,1,1,0,1,0,0,1,0,1]) # code tau = 1 # time acceleration factor Tstr = 10e-3 # transmitted symbol interval Ts = Tstr/tau # Nyquist's symbol interval td = 0.01 # initial delay of the sequence (time offset) # Time Domain a1 = gen.rcos_tr(t,Tstr,td + Tstr/2,cd,Ts,1.0) a2 = gen.rcos_tr(t,Tstr,td + Tstr/2,cd,Ts,0.5) a3 = gen.rcos_tr(t,Tstr,td + Tstr/2,cd,Ts,0.0) c = gen.rect_tr(t,Tstr,0,td,cd) # Correlate processor A1_c = signal.correlate(a1,a1,'full') A2_c = signal.correlate(a2,a2,'full') A3_c = signal.correlate(a3,a3,'full') C1_c = signal.correlate( c,a1,'full') C2_c = signal.correlate( c,a2,'full') C3_c = signal.correlate( c,a3,'full') CC_c = signal.correlate( c, c,'full')
##################### Parameters ######################
f_sampl = 50e3 # sampling frequency in kHz
T_int = 0.5 # entire signal length in ms
##################### Simulation ######################
t = np.arange(0, T_int, 1 / f_sampl) # time axis
f = ut.freq_fr_time(t) # frequency axis
tc = ut.corr_fr_time(t) # correlation time axis
cd = prn.gold_seq(3, 5, no_bits=500) # code
Ts = 10e-3 # Nyquist's symbol interval
tau = 0.3 # time acceleration factor
Tstr = Ts * tau # transmitted symbol interval
td = 0.05 # initial delay of the sequence (time offset)
# Time Domain
a1 = gen.rcos_tr(t, Tstr, td + Tstr / 2, cd, Ts, 1.0)
#c = gen.rect_tr(t,Tstr,0,td,cd)
print("Length of the signal", np.size(a1))
print(60 * '-')
print('CUDA correlator')
print(60 * '-')
p = profiler.Profile(signatures=False)
p.enable()
cc = corcud.corr_td_single(a1, a1)
p.disable()
p.print_stats()
print(60 * '-')
print(60 * '-')
def rcos_qpsk_map(t, data, s_rate, **args):
"""
Generates a baseband signal to modulate with QPSK and raised cosine pulses
:param t: time axis
:param data: binary sequence which is going to be mapped
:param s_rate: symbol rate of the transmitted baseband signal
:param args: optional arguments, see the table.
+----------+-------------+-----------+---------------------------------------------------+
| Key word | Possible | Default | Description |
| | values | | |
+==========+=============+===========+===================================================+
| tp | positive | | pulse width of a single symbol |
| | float | 1/b_rate | |
+----------+-------------+-----------+---------------------------------------------------+
| td | positive | | delay of the signal with reference to the origin |
| | float | 0 | of the time axis |
+----------+-------------+-----------+---------------------------------------------------+
| pw | positive | 1/b_rate | pulse width of the sinc - main lobe |
| | float | | |
+----------+-------------+-----------+---------------------------------------------------+
| alpha | positive | 0.8 | roll-off factor |
| | float | | |
+----------+-------------+-----------+---------------------------------------------------+
:return: Baseband signal
"""
tup = 2 # number of bits in one tuple
n_d = tup - (np.size(data) % tup)
data = np.append(data,
np.zeros(n_d)) # appends zeros to get the proper shape
data_2s = data.reshape(-1, tup) # reshaping the data vector into matrix
data_2s = data_2s > 0
## Baseband signal parameters
if 'tp' in args:
tp = args['tp']
else:
tp = 1 / s_rate # pulse width of a single symbol
if 'td' in args:
td = args['td']
else:
td = 0 # signal starts at time td = 0s
if 'pw' in args:
pw = args['pw']
else:
pw = 1 / s_rate # pulse width of the sinc - main lobe
if 'alpha' in args:
alpha = args['alpha']
else:
alpha = .8 # roll-off factor
# Baseband signal generator
i_bb = 2 * gen.rcos_tr(t, tp, td, data_2s[:, 0], pw, alpha) - 1
q_bb = 2 * gen.rcos_tr(t, tp, td, data_2s[:, 1], pw, alpha) - 1
bb = i_bb + q_bb * 1j
return (bb)