Patent ID: 11863362
Assignee: NORDIC SEMICONDUCTOR ASA
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method of decoding data from a radio signal, the method comprising:
applying a matched filter bank to a sampled radio signal to generate correlation-strength data, wherein each filter in the matched filter bank cross-correlates the sampled signal with data representing a respective filter sequence; and
using the correlation-strength data to generate a sequence of decoded symbols from the sampled signal wherein the value of each symbol in the sequence of decoded symbols is determined in part based on the value of a respective earlier decoded symbol from the sequence of decoded symbols;
wherein each filter sequence comprises a respective constant portion and a respective variable portion, the variable portion being positioned before the constant portion, wherein each constant portion is constant over time, and wherein each variable portion depends on one or more of the earlier decoded symbols;
wherein the method further comprises at least one of the following:
i) wherein, for each symbol in the sequence of decoded symbols, the respective earlier decoded symbol is offset from said symbol in time by a constant time offset; or
ii) wherein, when determining the value of a symbol of the sequence of decoded symbols, the variable portions are all equal to a common sequence of one or more earlier decoded symbols; or
iii) wherein the value of each symbol in the sequence of decoded symbols is determined in part based on the values of a plurality of respective earlier decoded symbols from the sequence of decoded symbols; or
iv) wherein the constant portions across all the filter sequences of the matched filter bank contain every integer value from zero to the number of filters in the matched filter bank minus one; or
v) wherein each symbol in the sequence of decoded symbols is decoded by applying the matched filter bank once, for each symbol, and identifying a best-matched filter, and decoding the symbol as the value in the filter sequence of the best-matched filter at a position corresponding to the symbol; or
vi) applying the matched filter bank to the sampled signal a plurality of times, with different respective time offsets, when decoding each symbol, and a hard symbol decision block determining a symbol of the decoded sequence by receiving a best-matched filter for each of the plurality of time offsets and decoding the value of the symbol position in the decoded sequence by applying a decision process to a respective plurality of symbol values corresponding to the symbol position from across the plurality of best-matched filters.