• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 31 subscribers
  • Views 1395 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CCS/AWR1243: AWR1243 cascade mmWave sensor’s FOV and angluar resolution ？

user4542591
Prodigy 240 points
Part Number: AWR1243

Tool/software: Code Composer Studio

Hi TI expert，

we have read the document 《Imaging Radar Using Cascaded mmWave Sensor Reference Design》；

First question：the document mentioned that awr1243 mmWave sensor‘s FOV is ±70°，how to calculate the sensor‘s FOV ？

second question：the document says that sensor‘s azimuth angular resolution is 1.4 degree，How to  calculate the azimuth angular resolution ？

the results achieved that 70*2/86 = 1.6279 degree, is it right ?


third question: the document says that sensor‘s elevation angular resolution is 18 degree，How to  calculate the elevation angular resolution ？

the document say the three elevation antennas are placed to form a minimum redundancy array, and the elevation angle resolution is equivalent to the resolution achieved with 7 antennas，

the elevation angluar resolution  =  lamda/(N*D) = 16.3702 degree, where is D = lamda/2, N = 7. the elevation FOV is N*resolution =  115 degree ？ is there right ？

nowadays， we want to improve elevation angluar resolution ？how we can do ?  

Increase antenna spacing or increase the number of antennas ? 

 

4th question： What are the benefits of the overlapped antenna in azimuth ？
 
many thanks！
 

 

 

 

  • 0
    TI__Guru 58035 points

    Hello,

    The FOV mentioned here is with reference to the antenna gain 6db point. Since the antenna spacing is lambda/2 the detectable FOV is actually +-90 deg, but since the antenna gain reduces with angle (~6dB at 70deg azimuth angle) we are quoting +-70deg FOV.

    The azimuth angular resolution is given my the number of virtual receiver channels. Since the antenna spacing is lambda/2 and number of virtual channels = 86 , the angular resolution is (2*180)/(86*3.14) = 1.33 deg. But we are quotng 1.4deg for practical  purposes.

    Over lapping antenna provide redundancy and the application could use them validate dynamic effects during the sensor operation.

    Regards,

    Vivek 

  • 0 in reply to Vivek Dham
    Prodigy 240 points

    Hi Vivek ，

    In the above reply，you didn't mentioned that the minimum redundant array，

    1. I'm dying to know how to calculate the 18 elevation angle degree of the 4-elements minimum redundant array ？

    2. what is the elevation FOV of awr1243 ？

    3. do you have any document about the  minimum redundant array ？

    4. how to improve elevation angluar resolution ？Increase antenna spacing or increase the number of antennas in the  minimum redundant array ? 

    5.the question https://e2e.ti.com/support/processors/f/791/p/762297/2837403?tisearch=e2e-sitesearch&keymatch=AWR1243%2525252520overlap#2837403 mentioned that

    the overlap channels are used to calculate the angle of arrival more accurately ？

    do you have any document about using overlaped antennas to  calculate the angle of arrival more accurately  and validate dynamic effects ？

     

    We look forward to your reply

    many thanks

     

  • 0 in reply to user4542591
    TI__Guru 58035 points

    Hello ,

    1. I'm dying to know how to calculate the 18 elevation angle degree of the 4-elements minimum redundant array ？

    <VD> with the non uniform antenna spacing in the elevation to form a minimum redundancy array the angular resolution is got by 360/(7*3.14).

     

    2. what is the elevation FOV of awr1243 ？

    <VD> As mentioned before the FoV is defined by the antenna and not the MMIC. For the antenna used on our cascade EVM, the 6dB gain points in the elevation plane are +-20deg

     

    3. do you have any document about the  minimum redundant array ？

    <VD> You can find lot of online material on this. Some reference is : https://authors.library.caltech.edu/80393/1/01139138.pdf

     

    4. how to improve elevation angluar resolution ？Increase antenna spacing or increase the number of antennas in the  minimum redundant array ?

    <VD> You can more antennas spaced in the elevation plan (now its only 4) to improve the angular resolution.

     

     5.the question https://e2e.ti.com/support/processors/f/791/p/762297/2837403?tisearch=e2e-sitesearch&keymatch=AWR1243%2525252520overlap#2837403 mentioned that the overlap channels are used to calculate the angle of arrival more accurately ？do you have any document about using overlaped antennas to  calculate the angle of arrival more accurately  and validate dynamic effects ？

    <VD> If there is a drift in the phase of different channels over temperature (for example) then this can be detected by over lap antennas and corrected for. If there is no phase mismatch across the channels that generate the overlap antennas , the over lap antennas will exactly overlap, but if there is a mismatch this will show up as a mismatch in the data received by these two channels.  You can find online material on this topic as well.

    regards,
    Vivek