Setup the Phaser for Radar

Radar Basics

Radar Simple Diagram

RADAR = Radio Detection And Ranging

  1. Radar transmits modulated EM-wave with an antenna

  2. Wave gets reflected at target

  3. Wave travels back to Radar receive antennas

  4. Receiver detects reflected wave

  5. Signal Processing estimates

    1. Distance (time delay)

    2. Angle of arrival (phase difference at multiple antenna elements)

    3. Velocity (Doppler shift)

Radar is Either Pulsed or Continuous

Pulsed Radar

  • High power, long range, radars

  • Timeline: First transmit, then turn off transmit, then receive

  • Energy = Power * Time

  • Generally uses the same antenna for both transmit and receive

  • Pulse compression used for range resolution

Pulsed Radar

Continuous Wave (CW) Radar

  • Simpler, lower cost, implementation

  • Simultaneous transmit and receive

  • Requires that the transit antenna be separate from the receive antenna

  • Best suited for short range applications

  • Most popular is FMCW (Frequency Modulated CW)

CW Radar

There’s many reasons why you would choose a CW or a pulsed radar. Both are commonly used to good effect. However, CW is always better at short range radar applications. Therefore, it is ideal to demonstrate radar concepts in a small lab environment.

Phaser Setup for Radar

Radar processing can be very computationally intensive. Therefore, while it is possible to run the radar labs on the Raspberry Pi, it is recommended that instead users connect the Phaser to a host computer as shown:

Radar Setup

  • An ethernet cable goes from the Raspberry Pi directly to the computer, or to the local network router

  • The center micro USB plug of Pluto goes to a USB-A port on the computer

  • The transmit antenna is connected to the OUT2 port

The transmit antenna is generally placed to the side of the receive array, and at the same height. As shown here:

Radar Setup

Radar Calibration

Prior to running any of these radar labs, be sure to complete the phased array calibration. This procedure is built into the MATLAB examples. But for python you’ll need to run the following two programs (place these files with the other files found here) and place the generated “pkl” files in the same folder as the other python radar examples.

  1. phaser_find_hb100

  2. phaser_cal You can find a video walkthrough of this material here:

Video

https://www.youtube.com/watch?v=igrN_wd_g74

Note

For questions or help with the Phaser, please visit: EngineerZone