Hi,
I would like to exercise my iwr1443 demo board with other parameters
other than the default values internal to the mmWave Demo Visualizer.
I have observed a number of inquires regarding this and I have learned
the following:
1. The possible parameters allowed in the demo board is limited but I
do not know what the limits are and none appear to be published. If
a non-allowed configuration is used, a return value of -1 in the
console window is provided with no insight which parameter is out of
limit and what the limit is.
2. The Sensing Estimator provides suitable parameters for the iwr1443
but as stated above, they may not work and the parameters (and
descriptions) provided are not clearly matched with the parameter
descriptions provided in the SDK user guide. Perhaps many of the
values provided by the estimator are informational.
One change from the default values I would like to explore is the
frame rate. The visualizer has an upper limit of 30. I would like to
go higher, lets say 100 fps. I realize that the number of chirps in a
frame would have to be reduced and/or limit the file size the uart can
send. One configuration file I would like to use but errors is this:
% ***************************************************************
% Created for SDK ver:01.01
% Created using Visualizer ver:2.0.0.0
% Frequency:77
% Platform:xWR14xx
% ***************************************************************
sensorStop
flushCfg
dfeDataOutputMode 1
channelCfg 3 1 0
adcCfg 2 1
adcbufCfg 0 1 0 1
profileCfg 0 77 7 7 107.05 0 0 36.89 1 256 5465 0 0 30
chirpCfg 0 0 0 0 0 0 0 1
chirpCfg 1 1 0 0 0 0 0 3
frameCfg 0 1 31 0 10.00 1 0
lowPower 0 0
guiMonitor 0 0 0 0 0 1
cfarCfg 0 2 8 4 3 0 1280
peakGrouping 1 1 1 1 229
multiObjBeamForming 1 0.5
clutterRemoval 1
calibDcRangeSig 0 -5 8 256
compRangeBiasAndRxChanPhase 0.0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0
measureRangeBiasAndRxChanPhase 0 1.5 0.2
sensorStart
I have noticed that
1. The SampleSwap value in the adcbufCfg line is 1 (from the
visualizer default values) but the SDK user manual states that only a
value of 0 allowed. This is confusing since it raises doubts about
the accuracy of other information in the SDK user manual.
2. It appears that two chipCfg lines are required. Can you tell me
what is happening? If I remove one of them from the visualizer
default case it will not work so I know that both are necessary.
3. The profileCfg values appear to be most critic. I have attempted to adjust these as required based upon the json file created by the sensing estimator which is
{
"platform": "IWR1443",
"num_rx": 3,
"num_tx": 1,
"tx_gain": 9,
"rx_gain": 9,
"frequency_range": "77 - 81",
"maximum_bandwidth": 4000,
"tx_power": 12,
"ambient_temperature_degC": 30,
"maximum_detectable_range": 20,
"range_resolution": 4,
"maximum_velocity_kmph": 30,
"velocity_resolution_kmph": 2,
"measurement_rate": 100,
"typical_detected_object": "Car",
"detection_loss": 1,
"system_loss": 1,
"implementation_margin": 2,
"detection_SNR": 12,
"maximum_radar_cube_size": 384,
"maximum_RF_bandwidth": 15,
"maximum_sampling_frequency": 18.75,
"sensor_maximum_bandwidth": 4000,
"maximum_allowed_bandwidth": 4000,
"starting_frequency": 77,
"maximum_velocity": 8.333333333333334,
"velocity_resolution": 0.5555555555555556,
"valid_sweep_bandwidth": 3750,
"idle_time": 7,
"adc_valid_start_time": 4.3,
"excess_ramping_time": 1,
"periodicity": 10,
"ambient_temperature": 303.15,
"noise_figure": 16,
"num_virtual_rx": 3,
"non_coherent_combining_loss": 0,
"rcs_value": 5,
"combined_factor_in_dB": -2,
"combined_factor_linear": 0.6309573444801932,
"inter_chirp_time": 12.3,
"aux_comp_coeff_a": 78875000000,
"aux_comp_coeff_b": -8013712.5,
"chirp_time": 101.6001584786054,
"ramp_slope_init": 36.90939124656643,
"ramp_slope_parameter": 764,
"ramp_slope": 36.885738372802734,
"aux_comp_T1": 1,
"maximum_beat_frequency": 4.918098449707031,
"sampling_frequency": 5.4645538330078125,
"number_of_samples_per_chirp": 556,
"total_sweep_bandwidth": 3948.4944133758545,
"idle_time_minimum": 7,
"ramp_end_time": 107.04664153577662,
"carrier_frequency": 77.15861127200186,
"aux_comp_T2": 3.3,
"adc_valid_start_time_2": 4.3,
"lambda": 3.8880948614073803,
"max_chirp_repetition_period": 117,
"chirp_repetition_period": 114,
"num_range_fft_bins": 1024,
"min_num_of_chirp_loops": 31,
"max_range_for_typical_detectable_object": 88.11544914293157,
"min_rcs_detectable_at_max_range": 0.013270330829623643,
"num_doppler_fft_bins": 32,
"active_frame_time": 3.534,
"range_inter_bin_resolution": 2.171875,
"velocity_inter_bin_resolution": 0.5381944444444444,
"radar_cube_size": 372
}
I have examined the mmwavelink doxgen and device datasheet for
guidance but it has been limited.
Please advise other sources or particular sections that I should
examine more closely. If you see any apparent discrepancy in my
configuration, please indicate the short coming.
Thanks.
Al