Wireless diversity receiving method

Abstract

The invention discloses a wireless diversity receiving method. A receiving end uses two or more antennas to simultaneously receive signals of different paths. The signals of all the paths are respectively amplified by a low-noise amplifier, input to a frequency mixer, converted into intermediate-frequency signals through the frequency mixer and input to an intermediate-frequency amplifier, and the intermediate-frequency amplifier amplifies the intermediate-frequency signals and outputs the intermediate-frequency signals through two paths; one path of signals is input to a demodulator, data demodulated by the demodulator is packed and sent to a MCU selector; the other path of signals is input to an ADC to be converted into RSSI parameters; and RSSI data output through a plurality of paths is sent to a MCU comparator, the MCU comparator determines a path of signals with the best RSSI parameters through comparison, and the MCU selector selects packed data of the path of signals with the best RSSI parameters as signal output. The effect of signal fading is mitigated, the quality of signal transmission is improved, and the undesirable phenomena such as off-and-on voice and video and data packet loss in wireless communication are overcome.

Description

[0001] technical field [0002] The present invention relates to the technical field of high-frequency communication reception, and more specifically, relates to a wireless diversity reception method suitable for wireless reception of wireless microphones, mobile video, mobile broadcast TV, Bluetooth, WiFi, etc. in a wireless local area network of 2.4 GHz. Background technique [0003] The wireless diversity reception method refers to the method that the receiving end performs specific selection processing on multiple signals with fading characteristics that are independent of each other (carrying the same information) received by it, so as to reduce the fluctuation of the signal level. The signal sent by the transmitting end is scattered and transmitted in space, and the receiving end uses dual antennas or multiple antennas to receive signals of different paths at the same time, as long as several signals are independent of each other, and then select the total signal wit...

AI Technical Summary

Problems solved by technology

[0004]The development and application in the wireless field has penetrated into people's life style and work, and people's requirements for wireless communication are getting higher and higher, especially the communication quality In daily life, with the development of wireless microphones, mobile TV, subway TV and other indoor and outdoor broadcasting fields, people have higher and higher requirements for the quality of sound and video, and in high data In the process of wireless transmission of large quantities, the transmitting device sends signals to the space. When the ground wave signal is blocked by multiple obstacles such as tall buildings, hills, and moving vehicles in the transmission path, reflection or scattering will occur, forming multiple signal arrivals. The receiving antenna, due to the different arrival times and phases of the receiving antenna, different signals of opposite phases are superimposed and weaken each other, resulting in signal fading, as shown in Figure 1, and the received signal is very weak, resulting in packet loss. Sound and video are choppy

When the receiver and the transmitter move towards each other, the frequency of the signal he receives is higher than the frequency of the transmission. On the contrary, when they move in opposite directions, the frequency of the signal received is lower than the frequency of the transmission, resulting in a Doppler shift. As shown in Figure 2, the fading it produces will make it difficult for the receiver to accurately resolve the signal

[0005] Among the above, the small-scale fading caused by multipath fading and Doppler frequency shift is extremely destructive to the received signal of mobile receiving equipment, and can cause large Intersymbol interference and vector changes in frequency, resulting in packet loss at the receiver and choppy audio and video

Such small-scale fading such as multipath fading and Doppler frequency shift is an inevitable problem, but now some receivers are single-channel receivers, large data transmission, often weak signals, lost data packets, audio and video unobstructed and other adverse phenomena

[0006]In various current wireless communications, with the development of DVB-T in mobile TV, car TV, building TV, subway TV, wireless microphone and other wireless fields, in these Within the receiving range, small-scale fading such as multipath fading and Doppler frequency shift is inevitable. Fading reduces the quality of signal transmission, which causes the sound received by the receiving device to be strong, weak, or intermittent. It will also be intermittent, or even unable to receive signals and other bad phenomena, but today's existing receiving equipment generally uses single-channel reception, which is greatly affected by fading, so it is easy to produce the above bad phenomena

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