Energy detection method and device combining time domain double thresholds and frequency domain variable point number

Abstract

The invention discloses an energy detection method and an energy detection device combining time domain double thresholds and a frequency domain variable point number. The method comprises the following steps of: performing primary detection by using a double-threshold energy detection method according to the characteristics of time domain energy detection and frequency domain energy detection; if statistical energy falls at the two ends of the two thresholds, making a judgment directly; if energy falls between high and low time domain thresholds, detecting by using frequency domain energy; and if energy falls between a low threshold and a variable point number partition threshold, performing frequency domain energy detection of N-point FFT (Fast Fourier Transform), otherwise performing frequency domain energy detection of point FFT. Due to the adoption of the energy detection method and the energy detection device, the aim of saving detection time consumption can be fulfilled while increasing the detection accuracy probability, the characteristics of time domain energy detection and frequency domain energy detection are combined, and frequency spectrum joint detection in a cognitive radio system is realized on the basis of time domain double thresholds.

Description

technical field [0001] The invention belongs to the field of communication technology, and in particular relates to a method and device for energy detection of combined time-domain double-threshold and frequency-domain variable point numbers in a cognitive radio system. Background technique [0002] With the rapid growth of demand for wireless communication services, available spectrum resources are increasingly scarce, and the shortage of spectrum resources has become one of the main bottlenecks in the development of wireless communication technologies. Even so, the utilization rate of the allocated spectrum resources by some licensed users is still low. The application of cognitive radio provides a good solution to improve spectrum utilization. Its core idea is that when licensed users are not using licensed frequency bands, cognitive users can use the licensed frequency band without causing interference to licensed users. frequency band for communication. Since cognitiv...

AI Technical Summary

Problems solved by technology

The time-domain energy detection algorithm is relatively simple to implement, and the detection timeliness is high, but the distortion and spectrum information of the detection signal cannot be obtained

The frequency domain energy detection algorithm introduces Fast Fourier Transformation (FFT, Fast Fourier Transformation), which can not only obtain the distortion degree of the detected signal from the spectrum, but also confirm whether the detected signal is a DVB-T signal, but the amount of processed data increases , and the larger the number of FFT transformation points, the larger the amount of processed data, and the longer the detection time

For example, the Chinese invention patent application with the announcement number CN101848044 discloses a "low power consumption time domain and frequency domain dual-threshold joint energy detection algorithm". However, when the signal-to-noise ratio is large, the algorithm still needs joint detection in the time domain and frequency domain, which takes a long time and requires a large amount of data to be processed.

Therefore, there is still no detection time consumption, detection accuracy, and algorithm complexity that meet the requirements of spectrum sensing technology in cognitive radio.

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