Estimation of incidence angles in phased antenna arrays
The representative embodiments discussed in the present disclosure relate to techniques in which the transmission and reception of phase array antennas may be measured to more accurately and more efficiently estimate incidence angles of the associated RF signals. More specifically, in some embodiments, RF signals may be transmitted and received by various subsets of antennas in a pair of phased antenna arrays, and the resulting signals may adaptively filtered and fed back to perform iterations until incidence angles may be accurately determined.
1. A method for determining incidence angles for a phased antenna array, the method comprising:
performing a first test by activating only a first subset of antennas in a transmitter phased antenna array and activating only a first subset of antennas in a receiver phased antenna array;
measuring incidence angles for the transmitter phased antenna array and for the receiver phased antenna array based on the first test;
performing a second test by activating only a second subset of antennas in the transmitter phased antenna array and activating only a second subset of antennas in the receiver phased antenna array;
measuring incidence angles for the transmitter phased antenna array and for the receiver phased antenna array based on the second test; and
repeating the first test and the second test until the incidence angles for the transmitter phased antenna array and for the receiver phased antenna array demonstrate substantially zero error.
2. The method, as set forth in claim 1 , wherein performing the first test comprises activating all odd antennas in the transmitter phased antenna array and activating all odd antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even antennas in the transmitter phased antenna array and activating all even antennas in the receiver phased antenna array.
3. The method, as set forth in claim 1 , wherein performing the first test comprises activating all odd antennas in the transmitter phased antenna array and activating all even antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even antennas in the transmitter phased antenna array and activating all odd antennas in the receiver phased antenna array.
4. The method, as set forth in claim 1 , wherein the transmitter phased antenna array comprises an N-by-N array, and wherein the receiver phased antenna array comprises an N-by-N array, where N is an integer of 2 or greater.
5. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array.
6. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array.
7. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd columns of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even columns of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array.
8. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd columns of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even columns of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array.
9. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all odd columns of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all even columns of antennas in the receiver phased antenna array.
10. The method, as set forth in claim 4 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all even columns of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all odd columns of antennas in the receiver phased antenna array.
11. An adaptive filter for determining incidence angles for a phased antenna array, the adaptive filter comprising:
a plurality of filter blocks, each respective filter block being adapted to measure incidence angles for a transmitter phased antenna array having a respective excitation vector and measure incidence angles for a receiver phased antenna array having a respective excitation vector, wherein each respective filter block is adapted to:
perform a first test by activating only a first subset of antennas in the transmitter phased antenna array and activating only a first subset of antennas in the receiver phased antenna array;
measure incidence angles for the transmitter phased antenna array and for the receiver phased antenna array based on the first test;
perform a second test by activating only a second subset of antennas in the transmitter phased antenna array and activating only a second subset of antennas in the receiver phased antenna array;
measure incidence angles for the transmitter phased antenna array and for the receiver phased antenna array based on the second test; and
repeat the first test and the second test until the incidence angles for the transmitter phased antenna array and for the receiver phased antenna array demonstrate zero error.
12. The adaptive filter, as set forth in claim 11 , wherein performing the first test comprises activating all odd antennas in the transmitter phased antenna array and activating all odd antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even antennas in the transmitter phased antenna array and activating all even antennas in the receiver phased antenna array.
13. The adaptive filter, as set forth in claim 11 , wherein performing the first test comprises activating all odd antennas in the transmitter phased antenna array and activating all even antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even antennas in the transmitter phased antenna array and activating all odd antennas in the receiver phased antenna array.
14. The adaptive filter, as set forth in claim 11 , wherein the transmitter phased antenna array comprises an N-by-N array, and wherein the receiver phased antenna array comprises an N-by-N array, where N is an integer of 2 or greater.
15. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array.
16. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array.
17. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd columns of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even columns of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array.
18. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd columns of antennas in the transmitter phased antenna array and activating all even rows of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even columns of antennas in the transmitter phased antenna array and activating all odd rows of antennas in the receiver phased antenna array.
19. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all odd columns of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all even columns of antennas in the receiver phased antenna array.
20. The adaptive filter, as set forth in claim 14 , wherein performing the first test comprises activating all odd rows of antennas in the transmitter phased antenna array and activating all even columns of antennas in the receiver phased antenna array, and wherein performing the second test comprises activating all even rows of antennas in the transmitter phased antenna array and activating all odd columns of antennas in the receiver phased antenna array.