1 This GNU Radio component implements a monostatic radar transmitter
2 and receiver. It uses a custom FPGA build to generate a linear
3 FM chirp waveform directly in the USRP. Echo returns are recorded
4 to a file for offline analysis.
6 The LFM chirp can be up to 32 MHz in width, whose center frequency
7 is set by which transmit daughter board is installed. This gives
8 a range resolution of approximately 5 meters.
10 The script to run is placed in $prefix/bin:
12 Usage: usrp_radar_mono.py [options]
15 -h, --help show this help message and exit
16 -T TX_SUBDEV_SPEC, --tx-subdev-spec=TX_SUBDEV_SPEC
17 use transmitter board side A or B (default is first
19 -R RX_SUBDEV_SPEC, --rx-subdev-spec=RX_SUBDEV_SPEC
20 use receiver board side A or B (default is first
22 -g GAIN, --gain=GAIN set gain in dB (default is midpoint)
23 -f FREQ, --frequency=FREQ
24 set transmitter center frequency to FREQ in Hz,
26 -w FREQ, --chirp-width=FREQ
27 set LFM chirp bandwidth in Hz, default is 32M
28 -a AMPLITUDE, --amplitude=AMPLITUDE
29 set waveform amplitude in % full scale, default is 15,
30 --ton=TON set pulse on period in seconds, default is 5e-06,
31 --tsw=TSW set transmitter switching period in seconds, default
33 --tlook=TLOOK set receiver look time in seconds, default is 5e-06,
34 --prf=PRF set pulse repetition frequency in Hz, default is
36 -v, --verbose enable verbose output, default is disabled
37 -D, --debug enable debugging output, default is disabled
38 -F FILENAME, --filename=FILENAME
39 log received echos to file
41 The transmitter creates an LFM chirp, evenly centered on the supplied frequency.
42 The four timing parameters are:
44 ton Chirp on time in seconds.
46 tsw Transmitter switching time in seconds. This the delay after the chirp
47 is transmitted before the receiver is enabled. These two (tsw and ton)
48 parameters determine the minimum range of the radar.
50 tlook The the amount of time in seconds the receiver is enabled to record
51 echo responses ("look" time). This parameter determines the maximum
52 radar range that can be measured, though transmitter power will also
53 limit return strength and practical range.
55 prf Pulse repetition frequency in Hz. This establishes to overall pulse
56 repetition period, which results in idle time between when the receiver
57 is turned off and the next transmitted chirp begins.
59 The transmitter is completed. The receive path is logging echo data to a supplied
60 file; however, no meta-data is logged.
62 This is experimental code.
65 Corgan Enterprises LLC
66 jcorgan@corganenterprises.com