#!/usr/bin/env python
#
# Copyright 2007 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
#
# GNU Radio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#
from gnuradio import gr, usrp
from gnuradio import eng_notation
from gr import gr_threading as _threading
n2s = eng_notation.num_to_str
txp_delay = 60 # Pipeline delay to turn on transmit mixer
rxp_delay = 76 # Pipeline delay to turn off transmit mixer
#-----------------------------------------------------------------------
# FPGA Register Definitions
#-----------------------------------------------------------------------
FR_RADAR_MODE = usrp.FR_USER_0 # Operational mode
bmFR_RADAR_MODE_RESET = 1 << 0 # bit 0: active high reset
bmFR_RADAR_TXSIDE = 1 << 1 # bit 1: use TX side A or B
#bmFR_RADAR_MODE_LP = 1 << 2 # bit 2: enable digital loopback
#bmFR_RADAR_MODE_DR = 1 << 3 # bit 3: enable on-board deramping
#bmFR_RADAR_MODE_MD = 1 << 4 # bit 4: enable echo metadata
#bmFR_RADAR_MODE_CHIRPS = 3 << 5 # bit 5,6: number of chirp center frequencies
bmFR_RADAR_DEBUG = 1 << 7 # bit 7: enable debugging mode
FR_RADAR_TON = usrp.FR_USER_1 # 16-bit transmitter on time in clocks
FR_RADAR_TSW = usrp.FR_USER_2 # 16-bit transmitter switch time in clocks
FR_RADAR_TLOOK = usrp.FR_USER_3 # 16-bit receiver look time in clocks
FR_RADAR_TIDLE = usrp.FR_USER_4 # 32-bit inter-pulse idle time
FR_RADAR_AMPL = usrp.FR_USER_5 # 16-bit pulse amplitude (2s complement) into CORDIC
FR_RADAR_FSTART = usrp.FR_USER_6 # 32-bit FTW for chirp start frequency
FR_RADAR_FINCR = usrp.FR_USER_7 # 32-bit FTW increment per transmit clock
FR_RADAR_ATRDEL = usrp.FR_USER_8 # 16-bit TX delay in clocks, 16-bit RX delay in clocks
# These are for phase II development (need to renumber)
#FR_RADAR_FREQ1N = usrp.FR_USER_8 # 24-bit N register for chirp #1
#FR_RADAR_FREQ1R = usrp.FR_USER_9 # 24-bit R register for chirp #1
#FR_RADAR_FREQ1C = usrp.FR_USER_10 # 24-bit C register for chirp #1
#FR_RADAR_FREQ2N = usrp.FR_USER_11 # 24-bit N register for chirp #2
#FR_RADAR_FREQ2R = usrp.FR_USER_12 # 24-bit R register for chirp #2
#FR_RADAR_FREQ2C = usrp.FR_USER_13 # 24-bit C register for chirp #2
#FR_RADAR_FREQ3N = usrp.FR_USER_14 # 24-bit N register for chirp #3
#FR_RADAR_FREQ3R = usrp.FR_USER_15 # 24-bit R register for chirp #3
#FR_RADAR_FREQ3C = usrp.FR_USER_16 # 24-bit C register for chirp #3
#FR_RADAR_FREQ4N = usrp.FR_USER_17 # 24-bit N register for chirp #4
#FR_RADAR_FREQ4R = usrp.FR_USER_18 # 24-bit R register for chirp #4
#FR_RADAR_FREQ4C = usrp.FR_USER_19 # 24-bit C register for chirp #4
#-----------------------------------------------------------------------
# Transmitter object. Uses usrp_sink, but only for a handle to the
# FPGA registers.
#-----------------------------------------------------------------------
class radar_tx(object):
def __init__(self, options):
self._subdev_spec = options.tx_subdev_spec
self._verbose = options.verbose
self._debug = options.debug
self._u = usrp.sink_s(fpga_filename='usrp_radar_mono.rbf')
if self._subdev_spec == None:
self._subdev_spec = usrp.pick_tx_subdevice(self._u)
self._subdev = usrp.selected_subdev(self._u, self._subdev_spec)
self._subdev.set_lo_offset(0.0)
self._ton_ticks = 0
self._tsw_ticks = 0
self._tlook_ticks = 0
self._tidle_ticks = 0
if self._verbose:
print "Using", self._subdev.name(), "for radar transmitter."
def set_ton(self, ton):
self._ton_ticks = 2*(int(ton*64e6)/2)-1 # Even number, then subtract 1
if self._verbose:
print "Setting pulse on time to", ton, " sec ("+`self._ton_ticks+1`+" ticks)"
self._u._write_fpga_reg(FR_RADAR_TON, self._ton_ticks)
def set_tsw(self, tsw):
self._tsw_ticks = 2*(int(tsw*64e6)/2)-1+rxp_delay # Even number, then subtract 1
if self._verbose:
print "Setting pulse switching time to", tsw, " sec ("+`self._tsw_ticks+1`+" ticks)"
self._u._write_fpga_reg(FR_RADAR_TSW, self._tsw_ticks)
def set_tlook(self, tlook):
self._tlook_ticks = 2*(int(tlook*64e6)/2)-1 # Even number, then subtract 1
if self._verbose:
print "Setting receiver look time to", tlook, " sec ("+`self._tlook_ticks+1`+" ticks)"
self._u._write_fpga_reg(FR_RADAR_TLOOK, self._tlook_ticks)
def set_prf(self, prf):
period = 2*int(32e6/prf)
self._tidle_ticks = period-(self._ton_ticks+self._tsw_ticks+self._tlook_ticks+3)-1
if self._verbose:
print "Setting PRF to", prf, "Hz ("+`self._tidle_ticks+1`+" ticks idle time)"
self._u._write_fpga_reg(FR_RADAR_TIDLE, self._tidle_ticks)
def set_amplitude(self, ampl):
self._amplitude = int(ampl*9946/100.0) # CORDIC gain correction
self._u._write_fpga_reg(FR_RADAR_AMPL, self._amplitude)
def set_freq(self, center_freq, chirp_width):
self._center_freq = center_freq
self._chirp_width = chirp_width
self._fstart = -int((chirp_width/2)*(2**32)/32e6)
self._fincr = int((chirp_width/16e6)*(2**32)/(self._ton_ticks+1))
if self._verbose:
print "Setting transmitter center frequency to", n2s(center_freq)
print "Setting chirp width to", n2s(chirp_width), "Hz "+"("+hex(self._fstart)+", "+hex(self._fincr)+")"
result = self._u.tune(0, self._subdev, center_freq)
if result == False:
raise RuntimeError("Failed to set transmitter frequency.")
self._u._write_fpga_reg(FR_RADAR_FSTART, self._fstart)
self._u._write_fpga_reg(FR_RADAR_FINCR, self._fincr)
def start(self):
self._u.start()
self._subdev.set_enable(True)
def stop(self):
self._subdev.set_enable(False)
self._u.stop()
def subdev_spec(self):
return self._subdev_spec
def echo_length(self):
return self._tlook_ticks+1
def __del__(self):
del self._subdev # Avoid weak reference error
#-----------------------------------------------------------------------
# Receiver object. Uses usrp_source_c to receive echo records.
#-----------------------------------------------------------------------
class radar_rx(gr.top_block):
def __init__(self, options, callback):
gr.top_block.__init__(self, "radar_rx")
self._u = None
self._subdev_spec = options.rx_subdev_spec
self._gain = options.gain
self._verbose = options.verbose
self._debug = options.debug
self._callback = callback
self._length_set = False
self._connected = False
self._frequency = 0.0
self._msgq = gr.msg_queue()
self._watcher = _queue_watcher_thread(self._msgq, self._callback)
def set_echo_length(self, length):
# Only call once
if self._length_set is True:
raise RuntimeError("Can only set echo length once.")
self._length = length
self._length_set = True
def tune(self, frequency):
if self._verbose:
print "Setting receiver frequency to", n2s(frequency)
self._frequency = frequency
if (self._u):
result = self._u.tune(0, self._subdev, frequency)
if result == False:
raise RuntimeError("Failed to set receiver frequency.")
def set_gain(self, gain):
self._gain = gain
if self._gain == None:
# if no gain was specified, use the mid-point in dB
g = self._subdev.gain_range()
self._gain = float(g[0]+g[1])/2
self._subdev.set_gain(self._gain)
def begin(self):
if not self._connected:
self._setup_connections()
if self._verbose:
print "Starting receiver..."
self.start()
def end(self):
if self._verbose:
print "Stopping receiver..."
self.stop()
self.wait()
if self._verbose:
print "Receiver stopped."
def _setup_usrp(self):
self._u = usrp.source_c(fpga_filename='usrp_radar_mono.rbf')
if self._subdev_spec == None:
self._subdev_spec = usrp.pick_rx_subdevice(self._u)
self._u.set_mux(usrp.determine_rx_mux_value(self._u, self._subdev_spec))
self._subdev = usrp.selected_subdev(self._u, self._subdev_spec)
if self._verbose:
print "Using", self._subdev.side_and_name(), "for radar receiver."
print "Setting receiver gain to", self._gain
self.set_gain(self._gain)
self.tune(self._frequency)
def _setup_connections(self):
if not self._length_set:
raise RuntimeError("Echo length not set.")
self._setup_usrp()
self._vblen = gr.sizeof_gr_complex*self._length
self._s2v = gr.stream_to_vector(gr.sizeof_gr_complex, self._length)
self._sink = gr.message_sink(self._vblen, self._msgq, False)
self.connect(self._u, self._s2v, self._sink)
if self._verbose:
print "Generating echo vectors of length", self._length, \
"(samples)", self._vblen, "(bytes)"
self._connected = True
class radar(object):
def __init__(self, options, callback):
self._verbose = options.verbose
self._debug = options.debug
self._mode = 0
self._trans = radar_tx(options)
self._rcvr = radar_rx(options, callback)
self.set_reset(True)
self.set_tx_board(self._trans.subdev_spec())
self.set_debug(self._debug)
self.set_atrdel()
def _write_mode(self):
self._trans._u._write_fpga_reg(FR_RADAR_MODE, self._mode)
def set_reset(self, value):
if value:
self._mode |= bmFR_RADAR_MODE_RESET
else:
self._mode &= ~bmFR_RADAR_MODE_RESET
self._write_mode()
def set_tx_board(self, tx_subdev_spec):
if tx_subdev_spec[0] == 1:
self._mode |= bmFR_RADAR_TXSIDE
else:
self._mode &= ~bmFR_RADAR_TXSIDE
self._write_mode()
def set_debug(self, value):
if value:
self._mode |= bmFR_RADAR_DEBUG
else:
self._mode &= ~bmFR_RADAR_DEBUG
self._write_mode()
def set_ton(self, ton):
self._trans.set_ton(ton)
def set_tsw(self, tsw):
self._trans.set_tsw(tsw)
def set_tlook(self, tlook):
self._trans.set_tlook(tlook)
self._rcvr.set_echo_length(self._trans.echo_length())
def set_prf(self, prf):
self._trans.set_prf(prf)
def set_amplitude(self, ampl):
self._trans.set_amplitude(ampl)
def set_freq(self, center_freq, chirp_width):
self._trans.set_freq(center_freq, chirp_width)
self._rcvr.tune(center_freq)
def set_atrdel(self, tx_delay=txp_delay, rx_delay=rxp_delay):
if self._verbose:
print "Setting TX delay of", tx_delay, "clocks, RX delay of", rx_delay
self._trans._u._write_fpga_reg(FR_RADAR_ATRDEL, tx_delay << 16 | rx_delay)
def start(self):
self.set_reset(False)
self._trans.start()
self._rcvr.begin()
def stop(self):
self._rcvr.end()
self._trans.stop()
self.set_reset(True)
#-----------------------------------------------------------------------
# Queue watcher. Dispatches received echos to callback.
#-----------------------------------------------------------------------
class _queue_watcher_thread(_threading.Thread):
def __init__(self, msgq, callback):
_threading.Thread.__init__(self)
self.setDaemon(1)
self._msgq = msgq
self._callback = callback
self._keep_running = True
self.start()
def run(self):
while self._keep_running == True:
msg = self._msgq.delete_head()
if self._callback:
self._callback(msg.to_string())