Optional-forward-link encoding method of ultra-high frequency reader

Abstract

The invention discloses an optional-forward-link encoding method of an ultra-high frequency reader. The optional-forward-link encoding method includes the steps of 1), determining an encoding clock of a forward link of the ultra-high frequency reader, determining the sampling frequency according to the encoding clock and calculating out a raised cosine filter conforming to the ultra-high frequency air interference protocol standard; 2), according to waveforms of step response of the raised cosine filter, taking multiple discrete points at least including the highest point and the lowest point in the ascending portion of the waveforms of the step response as ascend-descend edges of modulating signals and storing in a waveform look-up table; 3), according to the encoding mode of the ultra-high frequency air interface protocol standard, calculating out sampling points of high-low electrical levels of symbols corresponding to the encoded waveforms and storing in a sampling sustaining look-up table; 4), according to encoding control instructions sent by a controlled and received by the ultra-high frequency reader, taking out the quantized sampling points from addresses corresponding to the waveform look-up table and the sampling sustaining look-up table, and sending the sampling points according to the encoding clock.

Description

technical field [0001] The invention relates to a method for generating arbitrary waveforms, in particular to a coding method for the forward link of a reader in the field of RFID. Background technique [0002] With the continuous development of RFID technology, various standards emerge in an endless stream, and the encoding methods used are also varied. The baseband processing circuit of the reader must be designed for various encoding methods. [0003] In the existing baseband processing method of the reader, it is generally used to add a raised cosine filter to the baseband processing circuit to perform baseband shaping or directly OOK modulation without baseband shaping. Raising cosine shaping in baseband processing can overcome inter-symbol interference and reduce signal bandwidth occupation, but the circuit design is complex and takes up more resources, and the circuit needs to be modified for different RFID standards. Although the direct OOK modulation method without...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for any forward link encoding of a UHF reader to solve the problem that the existing reader baseband design method cannot meet the requirements of various standards

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