Method for testing a radio frequency (RF) data packet signal transceiver for proper implicit beamforming operation
Method for testing implicit beamforming operation of a radio frequency (RF) data packet signal transceiver device under test (DUT), including transmitting to the DUT combinations of a multidirectional (e.g., legacy) RF test signal and at least two unidirectional (e.g., beamformed) RF test signals with different signal directivity patterns, and monitoring signal strengths of signals received from the DUT in response to each signal. Signal directivity patterns can be controlled by transmitting multiple phase-controlled RF signals via separate arrays of multiple antenna elements to the DUT within a multipath RF signal environment, such as an electromagnetically shielded enclosure.
1. A method for testing implicit beamforming operation of a radio frequency (RF) data packet signal transceiver device under test (DUT), comprising:
transmitting, within a multipath RF signal environment via a plurality of antennas, a plurality of phase-controlled RF signals for reception by a DUT disposed at a DUT position within said multipath RF signal environment, including
transmitting one or more of said plurality of phase-controlled RF signals as a multidirectional RF test signal,
transmitting, via a first portion of said plurality of antennas, a first portion of said plurality of phase-controlled RF signals as a first substantially unidirectional RF test signal with a longitudinal signal axis in a first forward direction substantially toward said DUT position, and
transmitting, via a second portion of said plurality of antennas, a second portion of said plurality of phase-controlled RF signals as a second substantially unidirectional RF test signal with a longitudinal signal axis in a second forward direction substantially toward said DUT position; and
receiving, via said multipath RF signal environment and said plurality of antennas, a plurality of RF data packet signals transmitted by said DUT, including
receiving a multidirectional RF DUT signal,
receiving, via said first and second portions of said plurality of antennas, a first portion of said plurality of RF data packet signals as a first substantially unidirectional RF DUT signal with a longitudinal signal axis in a first reverse direction substantially toward said first portion of said plurality of antennas, and
receiving, via said first and second portions of said plurality of antennas, a second portion of said plurality of RF data packet signals as a second substantially unidirectional RF DUT signal with a longitudinal signal axis in a second reverse direction substantially toward said second portion of said plurality of antennas.
2. The method of claim 1 , wherein:
said first forward and reverse directions are substantially parallel and define a first wireless signal path,
said second forward and reverse directions are substantially parallel and define a second wireless signal path, and
said first and second wireless signal paths are nonparallel.
3. The method of claim 1 , wherein:
said receiving, via said first and second portions of said plurality of antennas, said first portion of said plurality of RF data packet signals as said first substantially unidirectional RF DUT signal with said longitudinal signal axis in said first reverse direction substantially toward said first portion of said plurality of antennas comprises receiving, via said first and second portions of said plurality of antennas, unequal first and second signal strengths, respectively; and
said receiving, via said first and second portions of said plurality of antennas, said second portion of said plurality of RF data packet signals as said second substantially unidirectional RF DUT signal with said longitudinal signal axis in said second reverse direction substantially toward said second portion of said plurality of antennas comprises receiving, via said first and second portions of said plurality of antennas, unequal third and fourth signal strengths, respectively.
4. The method of claim 3 , wherein:
said first signal strength is greater than said second signal strength; and
said fourth signal strength is greater than said third signal strength.
5. The method of claim 1 , wherein:
said multidirectional RF test signal comprises a nonbeamformed RF test signal;
said first substantially unidirectional RF test signal comprises a first beamformed RF test signal;
said second substantially unidirectional RF test signal comprises a second beamformed RF test signal;
said multidirectional RF DUT signal comprises a nonbeamformed RF DUT signal;
said first substantially unidirectional RF DUT signal comprises a first beamformed RF DUT signal; and
said second substantially unidirectional RF DUT signal comprises a second beamformed RF DUT signal.
6. The method of claim 1 , wherein:
said multipath RF signal environment comprises an interior region of a structure; and
said structure defines said interior region and an exterior region, and is configured to substantially isolate said interior region from electromagnetic radiation originating from said exterior region.
7. A method for testing implicit beamforming operation of a radio frequency (RF) data packet signal transceiver device under test (DUT), comprising:
receiving, with a DUT disposed at a DUT position within a multipath RF signal environment from a plurality of antennas, a plurality of phase-controlled RF signals, including
receiving one or more of said plurality of phase-controlled RF signals as a multidirectional RF test signal,
receiving a first portion of said plurality of phase-controlled RF signals as a first substantially unidirectional RF test signal with a longitudinal signal axis in a first forward direction from a first portion of said plurality of antennas substantially toward said DUT position, and
receiving a second portion of said plurality of phase-controlled RF signals as a second substantially unidirectional RF test signal with a longitudinal signal axis in a second forward direction from a second portion of said plurality of antennas substantially toward said DUT position; and
transmitting, with said DUT via said multipath RF signal environment, a plurality of RF data packet signals, including
transmitting a multidirectional RF DUT signal,
transmitting a first portion of said plurality of RF data packet signals as a first substantially unidirectional RF DUT signal with a longitudinal signal axis in a first reverse direction substantially toward said first portion of said plurality of antennas, and
transmitting a second portion of said plurality of RF data packet signals as a second substantially unidirectional RF DUT signal with a longitudinal signal axis in a second reverse direction substantially toward said second portion of said plurality of antennas.
8. The method of claim 7 , wherein:
said first forward and reverse directions are substantially parallel and define a first wireless signal path,
said second forward and reverse directions are substantially parallel and define a second wireless signal path, and
said first and second wireless signal paths are nonparallel.
9. The method of claim 7 , wherein:
said transmitting said first portion of said plurality of RF data packet signals as said first substantially unidirectional RF DUT signal with said longitudinal signal axis in said first reverse direction substantially toward said first portion of said plurality of antennas comprises transmitting, to said first and second portions of said plurality of antennas, unequal first and second signal strengths, respectively; and
said transmitting said second portion of said plurality of RF data packet signals as said second substantially unidirectional RF DUT signal with said longitudinal signal axis in said second reverse direction substantially toward said second portion of said plurality of antennas comprises transmitting, to said first and second portions of said plurality of antennas, unequal third and fourth signal strengths, respectively.
10. The method of claim 9 , wherein:
said first signal strength is greater than said second signal strength; and
said fourth signal strength is greater than said third signal strength.
11. The method of claim 7 , wherein:
said multidirectional RF test signal comprises a nonbeamformed RF test signal;
said first substantially unidirectional RF test signal comprises a first beamformed RF test signal;
said second substantially unidirectional RF test signal comprises a second beamformed RF test signal;
said multidirectional RF DUT signal comprises a nonbeamformed RF DUT signal;
said first substantially unidirectional RF DUT signal comprises a first beamformed RF DUT signal; and
said second substantially unidirectional RF DUT signal comprises a second beamformed RF DUT signal.
12. The method of claim 7 , wherein:
said multipath RF signal environment comprises an interior region of a structure; and
said structure defines said interior region and an exterior region, and is configured to substantially isolate said interior region from electromagnetic radiation originating from said exterior region.