Pseudorandom noise based channel coding scheme for tag to reader communication in UHF-RFID systems

This paper presents the capabilities of using Pseudorandom noise (PN) codes as a channel-coding scheme for the tag to reader communication. A comparative of the standardized coding scheme and the PN is presented. To take advantage of the PN code's orthogonality an example is shown using gold sequences of length 31 coding 16 symbols, which encodes the information that is backscattered by the tag. At the reader the corresponding correlation receiver is implemented to detect any of the 16 possible symbols. The decision is made using a maximum-likelihood method. This coding scheme will be compared to the EPCglobal GEN 2 standardized Miller codes in order to establish its advantages and disadvantages.