Decoding method of low intermediate frequency receiving system in short-range wireless network

Abstract

The invention relates to a decoding method for a low intermediate frequency receiving system in a short-range wireless network. The method comprises the following steps: firstly, receiving a radio-frequency signal transmitted by a transmitting terminal in the short-range wireless network, and directly sampling a low intermediate frequency signal after down-conversion to obtain a baseband receiving signal; carrying out correlative conjugating operation on a local spread-spectrum modulation complex sequence in the short-range wireless network to obtain a group of weight sequences; carrying out up-conversion on a first sequence of the local frequency-expansion modulation complex sequence to low intermediate frequencies; carrying out conjugate multiplication on the low intermediate frequency local sequence and a synchronous low intermediate frequency receiving signal to obtain a correlation value sequence; carrying out correlative operation on every weight sequence with the correlation value sequence respectively to obtain a group of correlation values; and taking the position of the sequence corresponding to the maximal correlation value as receiving demodulation data. The method has the advantages that secondary down-conversion does not need to be carried out on the receiving signal at a radio-frequency terminal, the complexity and the calculation amount of the system are reduced, image interference introduced by secondary conversion is reduced, conjugate multiplication is carried out only on the receiving signal and a first local sequence when decoding, and the calculation amount is reduced.

Description

technical field [0001] The invention relates to a decoding method for a low-intermediate frequency receiving system in a short-range wireless network, and belongs to the technical field of wireless communication. Background technique [0002] The receiving end in the wireless network needs to collect the wireless signal through the radio frequency circuit, and perform demodulation processing to restore the original data sent. [0003] In systems based on spread spectrum, the process of demodulation is the process of despreading the spread spectrum sequence. Spread spectrum sequences generally have good cross-correlation characteristics (that is, orthogonal characteristics). By using known spread spectrum sequences as the local reference signal of the receiver, the conventional demodulation method is to find the most correlated with the received sequence local reference signal to complete. When the spread spectrum sequence in the received signal is most correlated with a ce...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to propose a decoding method for a low-IF receiving system in a short-range wireless network. Under the premise of satisfying performance, a method for directly decoding low-IF receiving signals solves the complexity problem of real-time signal demodulation

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