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EVAL-DEMORAD and EVAL-TINYRAD can operate CW mode?

Category: Hardware


We consider that we would measure human vital using CW sensor.

Is EVAL-DEMORAD or EVAL-TINYRAD possible to operate as CW Doppler Radar?

If it isn't possible to operate as CW, could you provide that reason?

  • Hi,

    EVAL-DEMORAD is discontinued. I don't recommend using EVAL-DEMORAD.
    EV-TINYRAD24G is an updated version. You can use the FMCW Range Doppler feature to determine both range and doppler frequencies. 


  • Hi,

    Thanks for your reply. 

    We would like to put multiple radar sensor in the narrow area.

    We think that FMCW could cause interference for radio frequency since 24GHz has only 0.2GHz range frequency.

    On the other hand, CW sensor could avoid interference for radio frequency if the sensor can set multiple and different frequency channel on CW mode.

    So we would like to know that EV-TINYRAD24G could use as CW mode.

    Could you please consider again about using EV-TINYRAD24G as CW mode and provide the information?

    Best regards

  • Hi,

    Because some of the DSP processes are computed on embedded code, TinyRad can not operate CW mode. 

    In TinyRad, a sequence of linear chirp signals is transmitted out through AD5901, and the echoed signals by AD5904 are mixed with LO signals derived from the TX chip to generate the beat signal at the baseband. The ADC ADAR7251 samples the beat signals with a 1 MHz sampling rate and feeds to the digitized signal to the DSP BF706.

    As shown in the below figure, Embedded code transmits out 129 chirps, then mutes for a few milliseconds and repeats the same procedure to transmit out another 129 chirps, and so on. Each set of 129 chirps (or ramps) is called a frame. In each frame, the first chirp is used to synchronize the ADC sampling with the transmit signal, so each frame has 128 chirps captured by the ADC.

    The system parameters are set to the following values:

    • 1) 24 GHz carrier wavelength: λ = 0.0125 m
    • 2) Sweep bandwidth: ΔB = 180 MHz
    • 3) Range resolution:ΔR = 0.83m
    • 4) Velocity resolution: ∆V=λ/(2*N*Rtime)= 0.17 m/s, where N = 128 chirps.
    • 5) Angular resolution: Δθ= λ/D=0.66 rad. Width of Antenna Receive Array D=λ/2*(4-1)
  • Hi,

    Thanks for your explanation.

    TinyRad operates only FMCW mode by embedded code in DSP BF706.

    The FMCW operation by embedded code is shown in the figure below.

    Are we understanding this correct?

    We know that DemoRad has the same component as TinyRad.

    Does DemRad have the same embedded code in DSP?

    Is it impossible to operate CW mode with DemoRad?

    We know that DemoRad is discontinued,but we would like to know the possibility of CW mode.

    So could you confirm and provide the information?

    Best Regards

  • Hi,

    Q1: Yes,  you are. Embedded code in DSP BF706 handles Chirp signals.

    Q2: DemoRad and TinyRad have the same hardware with little different software. However, both of them are not capable of working in CW mode. 


  • Hi,

    Thanks for your answer.

    Is it impossible to change embedded code in DSP?

    If we could change embedded code in DSP, can we use as CW mode?

    Best Regards

  • Hi, 

    Sorry for the late response. I didn't get a notification about the reply.

    Unfortunately, the embedded code of the blackfin processor is not modifiable

    I would recommend checking EVAL-RADAR-MMIC2 board. This board consists of the same AFE as TinyRad.  EVAL-AD8283 Evaluation Board | Analog Devices or EVAL-ADAR7251 Evaluation Board | Analog Devices ADC converters can be used to convert IF signals to digital signals.

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