Cognitive OFDM (Orthogonal Frequency Division Multiplexing) based spectrum access method

Abstract

The invention discloses a cognitive OFDM (Orthogonal Frequency Division Multiplexing) based spectrum access method. The cognitive OFDM based spectrum access method comprises the steps of 1) configuring basic wireless communication parameters of a transmitting end and a receiving end, OFDM symbol parameters and a spectrum access allowance r of the transmitting end; 2) intercepting an effective signal in a section of signal length from a main channel before first transmission; 3) equally dividing all the data of array F generated in the second step into N groups according to a sequence; 4) generating a 01 sequence S containing N elements based on a frequency band verification standard; 5) determining whether to access at the moment by the transmitting end based on a frequency band verification sequence obtained in the fourth step; 6) distributing L valid subcarriers to one unoccupied frequency band by the transmitting end based on information represented by each bit in the frequency band verification sequence obtained in the fourth step, and performing zero-padding for the rest subcarriers; and 7) configuring the receiving end to obtain data from the transmitting end based on lead code information, and switching the receiving end to the main channel after first reception.

Description

technical field [0001] The invention relates to the field of wireless communication access, in particular to a wireless network access method for realizing fast access and improving frequency band utilization. Background technique [0002] In recent years, the rapid development and wide application of wireless communication have aggravated the problem of spectrum scarcity. Wireless communication needs to occupy spectrum resources. The traditional fixed spectrum resource division has made spectrum a scarce resource. Currently allocated spectrum is underutilized in most places and most of the time, while unlicensed bands are underutilized at the same time. Most of the allocated spectrum is underutilized both in time and space. [0003] In order to solve the contradiction between the low utilization rate of existing spectrum and the scarcity of spectrum resources, cognitive radio technology was proposed. Dynamically access the channel owned by the primary user for data transm...

AI Technical Summary

Problems solved by technology

[0008] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is how to propose a new wireless network user access method on the basis of not affecting the use of the wireless channel by the primary user, so as to improve the frequency band utilization of the wireless channel; How to perceive which frequency band resources have been used by the main user or have been seriously interfered by noise, and select the best spectrum segment that has not been occupied for access; how to ensure the reliability of wireless transmission for different users on the basis of solving the first two problems

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