Hardware Setup

Backend (C++)

To set up the complete system, you will need the following hardware:

• USRP Devices: 2 units (e.g., USRP X310, B210, etc.)
• Computers: 2 units (High performance recommended for signal processing)
• Antennas: 3 for downlink-only operation; 5 if duplex/uplink is enabled. The BS uplink RX path currently cannot share the same RF channel as the sensing RX path.
• OCXO/GPSDO: 2 units (Required for both USRPs)

Connection Setup

The system consists of two main nodes:

1. BS Node

   • Hardware: 1x Computer, 1x USRP.
   • Antennas: Connect 2 antennas for downlink-only operation (1 for downlink TX, 1 for sensing RX). If duplex/uplink is enabled, add a separate BS uplink RX antenna/RF chain; it cannot currently share the sensing RX channel.
   • Clock: Connect an OCXO or GPSDO to the REFIN port of the USRP.
   • Function: Transmits the OFDM signal and receives the radar echo.

2. UE Node

   • Hardware: 1x Computer, 1x USRP.
   • Antennas: Connect 1 antenna to the RX port for downlink-only operation. If duplex/uplink is enabled, also connect the UE TX antenna/RF chain; in FDD mode, ensure the configured uplink carrier is supported.
   • Clock: Connect an OCXO or GPSDO to the REFIN port of the USRP.
   • High-precision DAC (Optional): Use a high-precision DAC to enable finetuning the OCXO.
   • Function: Receives the OFDM signal for communication and bistatic sensing; when duplex/uplink is enabled, also transmits UE->BS uplink payloads.

Interface Requirements

To support high bandwidth and sample rates, ensure the connection between the Computers and USRPs uses:

• >= 10 Gigabit Ethernet (10GbE) (For X-series)
• USB 3.0 (For B-series)

Frontend (Python)

• Computer: 1x Computer (Windows or Linux).
  • Can be one of the backend computers or a separate machine.
• CPU: High performance CPU (i7 10700 or better) if no GPU is available.
• GPU: An Nvidia GPU is recommended for acceleration.