Patent ID: 8583067

Claim:
A system comprising: a wireless sensor configured to measure one or more characteristics associated with an industrial process; and a wireless node configured to receive wireless signals containing sensor measurements from the wireless sensor, the wireless node comprising a diversity receiver configured to process the wireless signals from the wireless sensor; wherein the diversity receiver comprises multiple channels, each channel comprising: a baseband signal generator configured to generate a baseband signal based on the received wireless signals, the baseband signal generator comprising an intermediate frequency-to-baseband converter configured to convert an intermediate frequency signal into the baseband signal; at least one offset corrector configured to receive the baseband signal and to correct frequency and phase offsets of the baseband signal to generate a corrected baseband signal; and a channel estimator configured to estimate channel coefficients using the corrected baseband signal; wherein the diversity receiver further comprises: a combiner configured to combine multiple outputs from the channels using the channel coefficients to generate a combined baseband signal; a demodulator configured to demodulate the combined baseband signal; and a time synchronizer configured to decimate the demodulated baseband signal; wherein the intermediate frequency-to-baseband converter in each channel is configured to store samples of its intermediate frequency signal in a first buffer, store products of the samples and cosine values in a second buffer, store products of the samples and sine values in a third buffer, store filtered products from the second buffer in a fourth buffer, and store filtered products from the third buffer in a fifth buffer; wherein the demodulator comprises (i) a limiter configured to store normalized complex values generated using the filtered products from the fourth and fifth buffers in a sixth buffer and (ii) a discriminator configured to store values generated using products of the normalized complex values and their delayed complex conjugates in a seventh buffer; and wherein the time synchronizer is configured to square the values from the seventh buffer, store the squared values in an eighth buffer, sum all same-indexed squared values from the eighth buffer to generate multiple sums that are stored in a ninth buffer, identify an index of a largest sum in the ninth buffer, and store samples of the demodulated baseband signal having the identified index in a tenth buffer.