BS YAML Reference

How to use this page

BS reads BS.yaml from its current working directory at startup. Copy a config/BS_*.yaml preset that matches your hardware and scenario, then edit the copy. Configuration is not hot-reloaded; restart the BS after making changes.

The tables follow the top-level YAML structure and use full paths such as uplink.arq_enabled to distinguish similarly named fields. A typical value is guidance, not a guaranteed default for every preset. If an optional section is omitted, the parser supplies its default values.

Keep coupled frame-structure, duplex, frequency, and resource-mapping fields consistent with the UE configuration.

Parameter tables

radio

Path	Type/Unit	Typical Value	Description
radio.radio_backend	string	uhd	Radio I/O backend. Use uhd for real USRPs or sim for the shared-memory channel simulator.

simulation

Path	Type/Unit	Typical Value	Description
simulation.session	string	oisac_sim	Shared simulator session namespace used by BS, UE, and ChannelSimulator.
simulation.enable_comm_rx	bool	true	Simulator produces the communication RX path for UE.
simulation.enable_sensing_rx	bool	true	Simulator produces monostatic sensing RX paths.
simulation.enable_uplink	bool	false	Simulator routes the UE-to-BS uplink stream.
simulation.pacing_enabled	bool	true	Pace simulator output to wall-clock sample time.
simulation.noise_power_dbfs	float / dBFS	-70	AWGN power per RX channel; very low values effectively disable noise.
simulation.snr_control_enable	bool	false	Scale the clean simulated signal before AWGN to maintain target_snr_db.
simulation.target_snr_db	float / dB	40	Initial SNR target when SNR control is enabled.
simulation.control_port	int	10002	ChannelSimulator ZMQ control port for runtime SNR commands.
simulation.cfo_hz	float / Hz	0	Initial BS-to-UE CFO before UE RX correction. The initial UE-to-BS CFO has the opposite sign, is carrier-ratio-scaled in FDD, and its residual then follows UE uplink TX retuning.
simulation.sample_rate_offset_ppm	float / ppm	0	UE sample-clock offset relative to the BS clock.
simulation.timing_offset_samples	int / samples	0	Constant integer sample delay injected on RX.
simulation.array_spacing_m	float / m	0.04283	Physical ULA element spacing; set <=0 to use array_spacing_lambda.
simulation.array_spacing_lambda	float / lambda	0.5	Legacy ULA spacing in wavelengths.
simulation.ring_capacity_samples	int / samples	262144	Per-stream shared-memory ring capacity.
simulation.steering_override_file	string	""	Optional array-manifold matrix file. When empty, the simulator generates a ULA manifold from angle_deg. When set, angle_deg no longer affects the array response; encode the angle-dependent amplitude and phase directly in the matrix.
simulation.comm_multipath_taps[]	object[]	optional	Communication tapped-delay-line taps with delay_samples, gain_db, and phase_deg.
simulation.targets[]	object[]	optional	Monostatic point scatterers with range_m, velocity_mps, gain_db, and angle_deg.
simulation.bistatic_targets[]	object[]	optional	Bistatic/communication point scatterers with the same target fields.

rf_sampling

Path	Type/Unit	Typical Value	Description
rf_sampling.sample_rate	float / Hz	50000000	Baseband sample rate.
rf_sampling.bandwidth	float / Hz	50000000	Analog bandwidth, usually matching sample_rate.

usrp_device

Path	Type/Unit	Typical Value	Description
usrp_device.device_args	string	addr=...	Shared USRP device args fallback.

clock_time

Path	Type/Unit	Typical Value	Description
clock_time.clock_source	string	external	Global clock source: internal, external, or gpsdo.
clock_time.time_source	string	internal	Global time/PPS source; empty follows clock_source.

Whenever the resolved BS clock_source is non-empty, CPU, CUDA, and HIP startup waits for one observed PPS transition, then arms the TX USRP and every distinct sensing/uplink RX USRP with set_time_next_pps(0). This includes time_source: internal on a single physical USRP; time_source selects the PPS input but does not disable startup alignment. When the resolved target set contains multiple distinct USRPs, every target must use time_source: external or gpsdo so they share a common PPS epoch; otherwise startup rejects the configuration before arming any device. Streaming starts only after every device time counter is observed to reset at the target edge, reports time_last_pps=0, and has a time_now value consistent with the other devices. A missing PPS, unsupported backend, or failed verification aborts startup instead of falling back to an arbitrary set_time_now(0) epoch. For gpsdo, this intentionally replaces any UTC-like device-time epoch with zero. The step removes the software-time-origin offset; it does not remove the X310 PPS capture quantization (5 ns at a 200 MHz master clock).

ofdm_frame

Path	Type/Unit	Typical Value	Description
ofdm_frame.fft_size	int	1024	OFDM FFT size.
ofdm_frame.cp_length	int / samples	128	Cyclic prefix length.
ofdm_frame.sync_pos	int	1	Sync symbol index inside each frame.
ofdm_frame.enable_sec_sync_symbol	bool	false	Reserve sync_pos-1 as a duplicate ZC sync symbol.
ofdm_frame.enable_cfo_training_sequence	bool	false	Reserve sync_pos+1 as a repeated CFO training field.
ofdm_frame.cfo_training_period_samples	int / samples	16	Repetition period of the CFO training field; must divide fft_size.
ofdm_frame.num_symbols	int	100	Number of OFDM symbols per frame.
ofdm_frame.sensing_symbol_num	int	100	Number of symbols used in sensing processing.
ofdm_frame.zc_root	int	29	Zadoff-Chu root for sync/preamble.
ofdm_frame.pilot_positions	int[]	[571,...]	Comb-pilot subcarrier indices.
ofdm_frame.midframe_pilot_symbols	int[]	[]	Optional in-frame BPSK pilot symbol indices.
ofdm_frame.midframe_pilot_seed	int	1296453708	Deterministic mid-frame BPSK pilot seed; must match TX/RX.

cuda

Path	Type/Unit	Typical Value	Description
cuda.cuda_precision_profile	string	fp32	fp32 preserves the existing path. mixed_fp16 uses FP16 for bulk OFDM FFT/IFFT storage and arithmetic while retaining FP32 for sensing, channel estimation, tracking, equalization, and sensitive reductions. Unsupported FP16 FFT shapes fall back to FP32.
cuda.cuda_mod_pipeline_slots	int	3	CUDA modulation pipeline slots; values below 1 are clamped.

ldpc

Path	Type/Unit	Typical Value	Description
ldpc.decoder_iterations	int	12	Maximum CPU LDPC iterations, at least 1; syndrome early stopping stays enabled.
ldpc.nms_normalization_factor	float	0.75	CPU NMS normalization factor, finite and in (0, 1]; Q16 requires multiples of 0.125.
ldpc.fixed_point	bool	false	Use the int16/Q16 layered-NMS CPU decoder instead of float32.
ldpc.fixed_point_scale	int	16	Power-of-two LLR scale before int16 saturation in fixed-point mode.

These fields configure CPU decoding on the BS uplink, for both float32 and Q16. Omitting them selects 12 iterations and a factor of 0.75. Explicit YAML values remain in effect; update both fields to use these defaults in an existing config. Edit them under LDPC decode in the Web Config Console, save, and restart the backend. Q16 supports 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875, 1.0; the LLR scale applies only when fixed_point: true. More iterations may improve error correction while increasing computation for weak signals.

downlink

Path	Type/Unit	Typical Value	Description
downlink.center_freq	float / Hz	2400000000	BS downlink RF center frequency.
downlink.tx_gain	float / dB	60	BS downlink TX gain.
downlink.tx_channel	int	0	BS downlink TX channel index.
downlink.tx_device_args	string	""	TX-specific device args; empty uses usrp_device.device_args.
downlink.tx_clock_source	string	""	TX clock source override.
downlink.tx_time_source	string	""	TX time source override.
downlink.wire_format_tx	string	sc16	TX wire format, typically sc16 or sc8.
downlink.tx_circular_buffer_size	int	32	Capacity of the modulated-frame queue feeding TX.
downlink.data_packet_buffer_size	int	256	Capacity of the encoded-packet buffer.
downlink.arq_enabled	bool	false	Enable downlink ARQ on the BS transmitter.
downlink.arq_window_packets	int	256	Downlink ARQ outstanding packet window; valid range 1–32767.
downlink.arq_retransmit_timeout_ms	int / ms	100	Downlink ARQ retransmission timeout.
downlink.arq_max_retries	int	5	Max downlink retransmission retries; 0 means unlimited within the window.

uplink

Path	Type/Unit	Typical Value	Description
uplink.enabled	bool	false	Master switch for the UE-to-BS uplink/duplex path.
uplink.duplex_mode	string	tdd	tdd uses an uplink symbol window; fdd uses uplink.center_freq and a full-frame uplink.
uplink.center_freq	float / Hz	2500000000	FDD-only uplink carrier. TDD uses the downlink center frequency.
uplink.symbol_start	int	90	TDD-only first uplink symbol in the downlink frame.
uplink.symbol_count	int	10	TDD-only uplink window length; 0 disables TDD uplink.
uplink.guard_symbols	int	1	TDD-only leading guard symbols inside the uplink window.
uplink.bs_dl_ul_timing_diff	int / samples	50	BS-side uplink RX window offset relative to the downlink TX frame anchor.
uplink.debug_self_channel	bool	false	Estimate local TX leakage/self channel from uplink RX windows for DUTI debugging.
uplink.ertm_to_enable	bool	false	Enable eRTM timing-offset payloads and UE-side TO logs.
uplink.ertm_report_interval_frames	int / frames	32	BS eRTM payload/report cadence in downlink TX frames; each report also refreshes the BS PPS anchor.
uplink.rx_gain	float / dB	0	BS uplink RX gain.
uplink.rx_channel	int	0	BS uplink RX channel index.
uplink.rx_wire_format	string	sc16	BS uplink RX wire format.
uplink.rx_device_args	string	""	Uplink RX device args override.
uplink.rx_clock_source	string	""	Uplink RX clock source override.
uplink.rx_time_source	string	""	Uplink RX time source override.
uplink.rx_agc_enable	bool	false	Enable BS uplink hardware RX AGC.
uplink.rx_agc_low_threshold_db	float / dB	14	Increase uplink RX gain below this filtered delay-spectrum peak threshold.
uplink.rx_agc_high_threshold_db	float / dB	16	Decrease uplink RX gain above this threshold.
uplink.rx_agc_max_step_db	float / dB	1	Maximum uplink RX gain step per AGC update.
uplink.rx_agc_update_frames	int	4	Minimum processed-uplink-frame interval between AGC updates.
uplink.equalizer_mode	string	mmse	BS uplink equalizer inverse mode: zf or mmse.
uplink.channel_tracking_mode	string	pilot_phase	Uplink per-symbol comb-pilot tracking mode: disabled or pilot_phase.
uplink.equalizer_mag_floor	float	1e-6	Lower bound for `
uplink.channel_tracking_min_pilot_snr	float	1e-4	Minimum comb-pilot residual weight before falling back.
uplink.arq_enabled	bool	false	Enable uplink ARQ on the BS receiver.
uplink.arq_ordered_delivery	bool	false	Buffer accepted uplink packets for in-order UDP delivery.
uplink.arq_window_packets	int	256	Uplink ARQ receive/reorder window; valid range 1–32767.
uplink.arq_feedback_interval_ms	int / ms	10	Minimum interval between uplink ARQ ACK feedback packets.

sensing

Path	Type/Unit	Typical Value	Description
sensing.rx_wire_format	string	sc16	Default sensing RX wire format.
sensing.rx_device_args	string	""	Default sensing RX args.
sensing.rx_clock_source	string	""	Default sensing RX clock source override.
sensing.rx_time_source	string	""	Default sensing RX time source override.
sensing.rx_channel_count	int	1	Number of monostatic sensing RX channels; 0 disables sensing RX.
sensing.rx_channels[]	object[]	see below	Per-channel sensing RX settings.
sensing.range_fft_size	int	1024	Range FFT size.
sensing.doppler_fft_size	int	100	Doppler FFT size.
sensing.view_range_bins	int	0	Backend RD view width; 0 means full range_fft_size.
sensing.view_doppler_bins	int	0	Backend RD view height; 0 means full doppler_fft_size.
sensing.output_mode	string	dense	dense uses STRD-based full output; compact_mask exports selected RE only.
sensing.on_wire_format	string	complex_float32	Sensing payload wire format.
sensing.backend_processing_enabled	bool	false	Publish backend RD/CFAR/micro-Doppler sidecars when supported.
sensing.symbol_stride	int	20	Default dense-mode STRD applied at startup.
sensing.paired_frame_queue_size	int	64	Per-channel RX/TX frame-pairing queue capacity.
sensing.mask_blocks	via resource_preview.mask_blocks	optional	Runtime sensing mask derived from resource preview.

sensing.rx_channels[] fields

Field	Type/Unit	Typical Value	Description
usrp_channel	int	1	USRP RX channel index for this sensing path.
device_args	string	""	Per-channel device args override.
clock_source	string	""	Per-channel clock source override.
time_source	string	""	Per-channel time source override.
wire_format	string	""	Per-channel wire-format override.
rx_gain	float / dB	30	Per-channel RX gain.
alignment	int / samples	63	Per-channel timing alignment offset.
rx_antenna	string	RX2	RX antenna port, such as RX1, RX2, or TX/RX.
enable_system_delay_estimation	bool	false	Run periodic ZC-based system-delay estimation and disable normal sensing for this channel.
enable_sensing_output	bool	inherits output switch	Per-channel monostatic output switch.
rx_cpu_core	int	-1	CPU core for the channel RX loop.
processing_cpu_core	int	-1	CPU core for the channel sensing-processing loop.

resource_preview

Path	Type/Unit	Typical Value	Description
resource_preview.data_resource_blocks[]	object[]	optional	Payload / sensing-pilot RE rectangles. Each item has kind, symbol_start, symbol_count, subcarrier_start, and subcarrier_count.
resource_preview.mask_blocks[]	object[]	optional	Compact sensing RE rectangles with symbol_start, symbol_count, subcarrier_start, and subcarrier_count.

measurement

Path	Type/Unit	Typical Value	Description
measurement.measurement_enable	bool	false	Enable internal PRBS measurement traffic.
measurement.measurement_mode	string	internal_prbs	Measurement generator/checker mode.
measurement.measurement_run_id	string	""	Run identifier written into measurement CSV summaries.
measurement.measurement_output_dir	string	""	Output directory for measurement CSV summaries.
measurement.measurement_payload_bytes	int / bytes	1024	Bytes per generated measurement payload.
measurement.measurement_prbs_seed	int	0x5A	Base seed for deterministic PRBS payload contents.
measurement.measurement_packets_per_point	int	1	Packets sent for one measurement epoch.
measurement.measurement_max_packets_per_frame	int	1	Max measurement packets pulled per frame; 0 means unlimited.

network_output

Path	Type/Unit	Typical Value	Description
network_output.udp_input_ip	string / IPv4	0.0.0.0	BS downlink payload UDP bind IP.
network_output.udp_input_port	int	50000	BS downlink payload UDP bind port.
network_output.udp_output_ip	string / IPv4	127.0.0.1	BS decoded uplink UDP destination IP.
network_output.udp_output_port	int	50003	BS decoded uplink UDP destination port.
network_output.udp_egress_pacer_enabled	bool	false	Enable queued pacing for decoded UDP egress.
network_output.udp_egress_pacer_target_mbps	float / Mbps	0	Egress pacer target rate; 0 auto-estimates from enqueue rate.
network_output.udp_egress_pacer_queue_packets	int	10240	Egress pacer queue capacity in datagrams.
network_output.udp_egress_pacer_max_delay_ms	float / ms	0	Max queued packet age; 0 disables age drops.
network_output.mono_sensing_output_enabled	bool	true	Enable monostatic sensing ZMQ output.
network_output.mono_sensing_ip	string / IPv4	0.0.0.0	Monostatic sensing/control ZMQ bind IP.
network_output.mono_sensing_port	int	8888	Monostatic sensing PUB port.
network_output.uplink_channel_ip	string / IPv4	0.0.0.0	BS uplink channel-estimate debug PUB IP.
network_output.uplink_channel_port	int	12358	BS uplink channel-estimate debug PUB port.
network_output.uplink_pdf_ip	string / IPv4	0.0.0.0	BS uplink delay-spectrum debug PUB IP.
network_output.uplink_pdf_port	int	12359	BS uplink delay-spectrum debug PUB port.
network_output.uplink_constellation_ip	string / IPv4	0.0.0.0	BS uplink constellation debug PUB IP.
network_output.uplink_constellation_port	int	12356	BS uplink constellation debug PUB port.
network_output.self_channel_ip	string / IPv4	0.0.0.0	BS self-channel debug PUB IP.
network_output.self_channel_port	int	12360	BS self-channel debug PUB port.
network_output.self_pdf_ip	string / IPv4	0.0.0.0	BS self-delay-spectrum debug PUB IP.
network_output.self_pdf_port	int	12361	BS self-delay-spectrum debug PUB port.
network_output.ertm_debug_ip	string / IPv4	0.0.0.0	eRTM debug PUB IP.
network_output.ertm_debug_port	int	12362	eRTM debug PUB port.
network_output.control_port	int	9999	ZMQ ROUTER port for runtime control.

cpu_cores

Path	Type/Unit	Typical Value	Description
cpu_cores.downlink_cpu_cores	int[]	[1,2,3,-1]	BS downlink cores: TX, modulation, LDPC encode, UDP receive.
cpu_cores.uplink_cpu_cores	int[]	[]	BS uplink cores: RX ingest, OFDM/LLR processing, LDPC decode + UDP output.
cpu_cores.main_cpu_core	int	-1	Main-thread CPU core; -1 disables binding.

logging

Profile timing dumps and diagnostic logs are gated by the hierarchical logging filter (not a separate profiling_modules key).

Path	Type/Unit	Typical Value	Description
logging.default_level	string	warn	Global verbosity: off / error / warn / info / debug.
logging.force_error	bool	true	Always emit unrecoverable Error lines.
logging.timestamps	bool	false	Prefix lines with local HH:MM:SS.uuuuuu.
logging.modules	map	{}	Per-module overrides. Debug modules inherit parents (e.g. mod, sensing, ertm). Performance modules end with _profiling (e.g. mod_profiling, sensing_profiling) and stay off until set explicitly.