PicoSenses Pipeline in Signal Processing Workflow

1. Signal Reception
   • The USRP or NIC captures Wi-Fi signals.
2. Signal Buffering
   • PicoScenes stores the received multi-channel signals in the Rx-side buffer.
3. Pipeline Processing
   • Pipelines fetch and decode Wi-Fi packets from the buffer.
   • Each pipeline can decode signals from a single channel or multiple channels.
   • Multiple pipelines work in parallel to decode signals from different channels.

Why MultiPipeline?

One breakthrough in Wi-Fi 7 is Multi-Link Operation (MLO), enabling devices to simultaneously access and use multiple frequency bands (e.g., 2.4 GHz, 5 GHz, 6 GHz). By intelligently scheduling data transmission at the link layer, MLO achieves parallel data transfer, significantly boosting throughput and reducing latency.

Similarly, PicoScenes provides a flexible framework for multi-pipeline configuration. Users can:

1. Process Multiple Channels in Parallel: Run pipelines simultaneously across different frequencies/channels.
2. Customize Pipelines: adjustable parameters:
   • Resampling rate
   • Bandwidth
   • Number of decoding threads
   • Carrier frequency offset (CFO) correction
   • Sampling frequency offset (SFO) compensation

How to Config MultiPipeline?

PicoScenes provides two command-line methods to set up Multi-Pipeline:

1. --rx-pipe

Assigns receive (Rx) channels to pipelines.

Syntax:

• Separate different pipelines with commas ,
• Assign multiple channels to one pipeline with underscores (_).

Note:

• Channel numbers must match those in --rx-channel.
• Cannot be used with --rx-pipe-cfg-file (this will override --rx-pipe).
• Only assigns channels—other parameters (bandwidth, decoding threads, etc.) remain unchanged.

Example:

Two pipelines, one channel each:

PicoScenes -d debug -i usrp --mode logger --rate 100e6 --rx-cbw 40 --rx-resample-ratio 0.4 --rx-freq 5190,5230 --rx-channel 0,1 --rx-pipe 0,1

Single pipeline, two channels:

PicoScenes -d debug -i usrp --mode logger --rate 100e6 --rx-cbw 40 --rx-resample-ratio 0.4 --rx-freq 5190,5230 --rx-channel 0,1 --rx-pipe 0_1

2. --rx-pipe-cfg-file

Specify the JSON config file path.The config file specify receive (Rx) channel(s) and other property config to each pipeline.

Format:

1. The file content like:

[
  {
  	pipeline1 config
  },
  {
  	pipeline2 config
  },
  ...
]

2. the property :

   rx-channel :must be specified,can be single channel number or multi channel number. Specify the pipeline occupied which channels.

​ Other parameters have default value: rx-resample-ratio = 1 rx-cbw = 20 rx-iq-mismatch = [0,0] mt = 1 sfo = 0 cfo = 0

Example:

PicoScenes -d debug -i usrp --mode logger --rate 100e6  --rx-freq 5230,5190 --rx-channel 0,1 --rx-pipe-cfg-file ~/cfg.json

~/cfg.json: The content bellow specify a pipeline occupies 0,1channel, both use rx-resample-ratio=0.2,mt=8,rx-cbw=20.

[
    {
        "rx-channel": [0,1],
        "rx-resample-ratio": 0.2,
        "rx-cbw": 20,
        "mt": 8,
    }
]

~/cfg.json: The content bellow specify two pipelines occupy channels 0 and 1 respectively,and each has more detailed parameter configurations.

[
  {
  "rx-channel": 0,
  "rx-resample-ratio": 0.4,
  "rx-cbw": 40,
  "mt": 8,
  "cfo": 0,
  "rx-iq-mismatch": [0,0]
  },
  {
  "rx-channel": 1,
  "rx-resample-ratio": 0.4,
  "rx-cbw": 40,
  "mt": 4,
  "sfo": 0
  }
]