SYSTEMS AND METHODS FOR JOINT BEAMFORMING AND PREAMBLE DETECTION
First Claim
1. An RFID reader system, comprising:
- an antenna array comprising a plurality of antenna elements;
a joint beamformer and preamble detector configured to receive inputs from each of the plurality of antenna elements, where the joint beamformer and preamble detector is configured to;
correlate the inputs from the plurality of antenna elements against a correlation sequence at a plurality of starting sample positions and a plurality of predetermined rates;
use the correlations to select a starting sample position and rate for decoding the received signal;
use the correlations to determine beamforming coefficients for combining the inputs from each of the plurality of antenna elements; and
resample the combined inputs from each of the plurality of antenna elements based upon the selected starting sample position and rate;
a decoder configured to receive the resampled signal from the joint beamformer and preamble detector and to decode data using the resampled signal.
6 Assignments
0 Petitions
Accused Products
Abstract
Systems and methods for reading RFID tags using joint beamforming and preamble detection in accordance with embodiments of the invention are disclosed. One embodiment includes an antenna array comprising a plurality of antenna elements, a joint beamformer and preamble detector configured to receive inputs from each of the antenna elements, and a decoder configured to receive a resampled signal from the joint beamformer and preamble detector and to decode data using the resampled signal. In addition, the joint beamformer and preamble detector is configured to correlate the inputs from the antenna elements against a correlation sequence at a plurality of starting sample positions and predetermined rates, use the correlations to select a starting sample position and rate for decoding the received signal, use the correlations to determine beamforming coefficients for combining the inputs, and resample the combined inputs based upon the selected starting sample position and rate.
-
Citations
16 Claims
-
1. An RFID reader system, comprising:
-
an antenna array comprising a plurality of antenna elements; a joint beamformer and preamble detector configured to receive inputs from each of the plurality of antenna elements, where the joint beamformer and preamble detector is configured to; correlate the inputs from the plurality of antenna elements against a correlation sequence at a plurality of starting sample positions and a plurality of predetermined rates; use the correlations to select a starting sample position and rate for decoding the received signal; use the correlations to determine beamforming coefficients for combining the inputs from each of the plurality of antenna elements; and resample the combined inputs from each of the plurality of antenna elements based upon the selected starting sample position and rate; a decoder configured to receive the resampled signal from the joint beamformer and preamble detector and to decode data using the resampled signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A method of detecting data transmitted by an RFID tag using an RFID receiver comprising an antenna array and a joint beamformer and preamble detector, comprising:
-
receiving sampled streams from each antenna element in the antenna array using the RFID receiver; correlating each stream against a predetermined correlation sequence for each of a plurality of possible starting samples and at each of a plurality of predetermined rates using the joint beamformer and preamble detector; summing the magnitude of the correlation value of each sample position and rate across each of the antenna streams using the joint beamformer and preamble detector; selecting the sample position and rate having the highest sum of correlation value magnitudes using the joint beamformer and preamble detector; determining beamforming coefficients based on the correlations of each stream at the selected sample position using the joint beamformer and preamble detector; combining the antenna outputs based upon the beamforming coefficients using the joint beamformer and preamble detector; resampling the combined antenna outputs based upon the selected starting sample and rate using the joint beamformer and preamble detector to produce a resampled signal; and decoding the transmitted data based upon the resampled signal using the RFID receiver.
-
Specification