A multi-channel receiving system

Abstract

This invention discloses a multi-channel receiving system. The system comprises an N-element low-frequency antenna, an M-element high frequency antenna, N+M low-noise amplifiers, a switched network unit, a down-conversion unit, a digital processing unit and two local-oscillation power-division networks. The down-conversion unit comprises echo input ends of L channels, local-oscillation signal input ends of L channels, and intermediate-frequency output ends of L channels. N, M and L are all positive integers; and L is not less than the larger value of N and M. One end of each of N+M low-noise amplifiers is connected with the N-element low-frequency antenna and the M-element high frequency antenna, and the other end is connected with N+M input ends of the switched network unit; L output ends of the switched network unit are connected with echo input ends of L channels. The formula is as shown in the description. The local-oscillation signal input ends of the channels are connected with the first local-oscillation power-division network; the formula is as shown in the description; the local-oscillation signal input ends of the channels are connected with the second local-oscillation power-division network; and the intermediate-frequency output ends of L channels are connected with L input ends of the digital processing unit.

Description

technical field [0001] The invention relates to a multi-channel receiving system in the technical field of signal receiving in radar, communication and electronic countermeasure systems, in particular to an ultra-wideband low-cost reconfigurable multi-channel receiving system based on DBF technology. Background technique [0002] The receiver detects useful echo signals from the noise, clutter and interference signals received by the antenna front, and performs necessary processing, and converts the echo signals into intermediate frequency signals through frequency conversion and sends them to the digital receiver for digital domain processing. A receiving system mainly includes three components: channel receiver, frequency source, and digital receiver. The channel receiver is mainly composed of a low-noise amplifier and a down-conversion unit. The frequency source provides signals such as local oscillator signals and reference clocks. The digital receiver digitizes the anal...

AI Technical Summary

Problems solved by technology

Although the sub-array digitalization method can effectively reduce the number of channels and thus reduce the cost, this design method is often accompanied by the sacrifice of DBF performance indicators

[0005] 2. In the implementation of conventional ultra-wideband receiving systems, often because the working bandwidth is too wide, and there are restrictions on overall indicators and functional requirements, sometimes it is necessary to use two ultra-wideband antennas to combine high and low frequency bands to realize the system working bandwidth

In order to realize the original functions in the entire working frequency band, the increase in the number of physical channels of the antenna will lead to an increase in the number of corresponding receiving channels, and the cost will rise rapidly

[0006] 3. In the implementation of a conventional UWB receiving system, the maximum instantaneous operating bandwidth of the system is limited by the channel design and the performance index of the A / D sampling device. To achieve a wider instantaneous operating bandwidth, it is necessary to sacrifice the channel index to a certain extent and improve the A / D sample rate implementation

However, the cost of high-end ultra-high-speed A / D sampling devices differs greatly from that of conventional A / D devices.

[0007] The number of antenna units in an ultra-wideband receiving system often corresponds to the number of receiving channels, which makes the cost high. However, the instantaneous working bandwidth of the system is limited by device performance indicators and channel design and cannot achieve wider bandwidth. Conventional ultra-wideband The single working mode of the receiving system cannot meet the contemporary needs for low-cost, high-performance radar, so it is necessary to design a low-cost multi-working mode ultra-wideband multi-channel receiving system

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