AWR2944EVM: Range estimation AWR2944 IC

Hello Dinesh,

Please reference this document for a good intro to range equations, including based on SNR and on chirp parameters.  Please reference 2.1.1:

Programming Chirp Parameters in TI Radar Devices (Rev. A)

this app note also gives some good idea of what you can expect for range based on different objects, as tested in the field:

mmWave Radar Sensors: Object Versus Range (Rev. A) (ti.com)

I think you may be worrying about increased path loss as antennas get closer to the ground.  However, generally you don't have to worry about this until the distance is far greater than the SNR limited range.  i.e. for the ranges typically used by a radar, the path loss exponent for 7m height is still similar to that of free space.  this article may be of interest here: Two-ray ground-reflection model - Wikipedia 

Hello James,  Thanks for the article, it really helps. We have selected AWR2944 IC, as we did checked the evaluation board AWR2944BOOST EVM results in the article TIDEP-01027, Distance coverage up to 200 meters and mounted on the rear end of the mid size car. What if we can place above 7m height from the ground. I beleive that distance can affect. Is there any testing results available by placing 2m to 7m height vary with tilt angle? Is there any calculation available to the find distance if we place the antenna above from the ground up to 7 meter ?

Hi Dinesh,

I don't expect you would see too much difference in the range for the mounting heights you are talking about.  The path loss exponent should still be roughly 2 for an uncluttered environment.  

Generally the range depends most on the following parameters:

1. Chirp configuration.   For higher range need larger IF bandwidth and/or smaller chirp slope

2. TX Output Power.  Typically should be 10 - 13 dBm for AWR devices.

3. TX Antenna Gain:  Typically should be 9 - 23 dBi recommended.  Higher gain will give higher range.  Shor range radar typically has ~9dBi gain, medium range radar 14-15dBi gain, and long range radar typically 21+ dBi gain.  

4. Radio Cross Section (RCS) of the target.  Typically is 0.1m2 to 50m2 (-10 dBmsm to 17 dBsm)

5. RX Antenna gain:  typically should be 9 dBi to 23 dBi.  High gain gives longer range.  similar for TX gain.   

6. Nois Figure:  typically 11 - 18 dB for AWR devices, but will be implementation dependent. 

7.  Active frame time:  typically 2 ms to 20 ms. 

8.  Detection SNR:  should be 10 dB to 18 dB typically for the target you want to detect.  

As a rule of thumb, 3dB SNR reduction will be 15 % less range, and 12 dB loss of SNR will be 50% less range.  

Regards,

James