Search

CN-117220707-B - Phased array radio frequency front end

CN117220707BCN 117220707 BCN117220707 BCN 117220707BCN-117220707-B

Abstract

The application discloses a low-cost phased array radio frequency front end which comprises an array antenna, a radio frequency link 1, a radio frequency link 2, a feed network, a frequency conversion module and a control module. The array antenna comprises antenna units and antenna subarrays. Each radio frequency link 1 is connected with 1 antenna subarray, each radio frequency link 2 is connected with 1 path of antenna unit, and the 1 antenna subarray comprises L antenna units. When the radio frequency front end works in the low frequency band f1-f3, the radio frequency link 1 and the radio frequency link 2 work simultaneously, all antenna units connected with the radio frequency link 1 and the radio frequency link 2 work to realize multiplexing of frequency and aperture, and when the radio frequency front end works in the high frequency band f3-f2, only the antenna unit connected with the radio frequency link 2 works. The application gives consideration to the gain of high and low frequency of the broadband radio frequency front end, avoids the waste of antenna aperture resources, reduces the number of radio frequency channels, saves the cost and has wide application prospect.

Inventors

  • LI XIANGXIANG
  • ZHANG WEI
  • LI YUE
  • TAO JING
  • WU HUIFENG
  • LI YEQIANG
  • XIANG YONGHUA

Assignees

  • 中国船舶集团有限公司第七二三研究所

Dates

Publication Date
20260512
Application Date
20230901

Claims (6)

  1. 1. The phased array radio frequency front end is characterized by comprising an array antenna, a radio frequency link 1, a radio frequency link 2, a feed network, a frequency conversion module and a control module; the array antenna comprises m antenna units A and n antenna subarrays B, wherein each antenna subarray B comprises L antenna units A, the total of the array antenna is m+n.L antenna units, the aperture size of an antenna formed by the m antenna units A is SA, the aperture formed by the n antenna subarrays B is SB, and the working bandwidth of the array antenna is f1-f2; The antenna subarray B is connected with the radio frequency link 1, the antenna unit A is connected with the radio frequency link 2, the whole radio frequency front end is provided with n radio frequency links 1 and m radio frequency links 2 in total, the radio frequency link 1 and the radio frequency link 2 are connected with the feed network, the feed network is connected with the frequency conversion module, and the control module controls radio frequency switches in the radio frequency link 1 and the radio frequency link 2; The radio frequency link 1 comprises a 1-way L power divider, a T/R component 1, a filter 1 and a single-pole single-throw radio frequency switch, wherein the 1-way L power divider is connected with the T/R component 1, the T/R component 1 is connected with the filter 1, the filter 1 is connected with the single-pole single-throw radio frequency switch, and the working bandwidth of the T/R component 1 is f1-f3, wherein f3 is smaller than f2; The radio frequency link 2 comprises a single-pole double-throw radio frequency switch, a T/R component 2, a T/R component 3, a filter 1, a filter 2, two single-pole single-throw radio frequency switches and a 1-way power divider, wherein the single-pole double-throw radio frequency switch is connected with the T/R component 2 and the T/R component 3, the T/R component 2 is connected with the filter 1, the filter 1 is connected with one single-pole single-throw radio frequency switch, the T/R component 3 is connected with the filter 2, the filter 2 is connected with the other single-pole single-throw radio frequency switch, the two single-pole single-throw radio frequency switches are connected with the 1-way power divider, the working bandwidth of the T/R component 2 is f1-f3, and the working bandwidth of the T/R component 3 is f3-f2; The T/R assembly comprises a receiving and transmitting change-over switch, a power amplifier, an attenuator, a phase shifter and a low noise amplifier, and is used for realizing the functions of power amplification and amplitude phase adjustment in a receiving and transmitting state; The feed network is used for carrying out equal-amplitude and equal-phase distribution on radio frequency signals; The frequency conversion module comprises up-down conversion, excitation signals are transmitted to the feed network after up-conversion when the radio frequency front end transmits, are distributed by the feed network and are transmitted to the radio frequency link and the antenna to radiate to free space, and signals received from the antenna are transmitted to the feed network through the radio frequency link when the radio frequency front end receives, and then are subjected to down-conversion to output intermediate frequency signals.
  2. 2. The phased array rf front-end of claim 1, wherein the number of antenna elements in antenna subarray B, l= (f 2/f 3)/(2), f2/f3 is an integer.
  3. 3. A phased array RF front end as claimed in claim 1, wherein, When the radio frequency front end operates at f1-f3, there are several modes of operation: The independent working mode of the radio frequency link 1 is that the control module controls the single-pole single-throw radio frequency switch of the radio frequency link 1 to be switched on, all the radio frequency switches of the radio frequency link 2 to be switched off, the aperture of a working radio frequency front end antenna is SB, and the number of radio frequency channels is n; The independent working mode of the radio frequency link 2 is that the control module controls the single-pole single-throw switch of the radio frequency link 1 to be turned off, the single-pole double-throw radio frequency switch of the radio frequency link 2 is turned on the T/R assembly 2, all the single-pole single-throw radio frequency switches are turned on, the aperture of the working radio frequency front end antenna is SA, and the number of radio frequency channels is m; The control module controls the single-pole single-throw radio frequency switch of the radio frequency link 1 to be connected, the single-pole double-throw radio frequency switch of the radio frequency link 2 is connected with the T/R component 2, all the single-pole single-throw radio frequency switches are connected, at the moment, the aperture of the working radio frequency front end is SA+SB, the aperture multiplexing and the frequency multiplexing of the radio frequency link are realized, and the number of radio frequency channels is m+n; When the radio frequency front end operates at f3-f2, only one mode of operation: the independent working mode of the radio frequency link 2 is that the control module controls the single-pole single-throw switch of the radio frequency link 1 to be turned off, the single-pole double-throw radio frequency switch of the radio frequency link 2 is turned on the T/R assembly 3, all the single-pole single-throw radio frequency switches are turned on, the aperture of the working radio frequency front end antenna is SA, and the number of radio frequency channels is m.
  4. 4. A phased array radio frequency front end as claimed in claim 3, wherein when the radio frequency front end is operated in the mode of f1-f3, the radio frequency link 1 and the radio frequency link 2 are operated simultaneously, the phase of the radio frequency signal after passing through the radio frequency link 1 is equal to the phase of the radio frequency signal after passing through the radio frequency link 2.
  5. 5. A phased array radio frequency front end as claimed in claim 3, wherein when the radio frequency front end is operated in the mode of f1-f3, the radio frequency link 1 and the radio frequency link 2 are operated simultaneously, the output power of the radio frequency signal after passing through the radio frequency link 1 is equal to the output power of the radio frequency signal after passing through the radio frequency link 2.
  6. 6. The phased array radio frequency front end of claim 1, wherein the bandwidth of the 1-way L-way power divider is f1-f3, the passband of the filter 1 is f1-f3, the passband of the filter 2 is f3-f2, and the bandwidth of the 1-way 2-way power divider is f1-f2.

Description

Phased array radio frequency front end Technical Field The application relates to the technical field of phase control, in particular to a phased array radio frequency front end. Background As phased arrays evolve toward broadband, the antenna element spacing becomes smaller, resulting in a dramatic increase in the number of radio frequency channels and an increase in cost. Moreover, the number of the radio frequency channels is huge, the resource intensive degree is insufficient, the system multi-task concurrency degree and the multi-functional resource multiplexing rate are limited, and the economical efficiency is poor. In order to reduce the cost of the rf front-end, reducing the number of rf channels is the most straightforward approach. The most dominant methods for reducing the number of radio frequency channels at present are sparse array and subarray level phased arrays. Sparse arrays have been widely studied and used in narrowband array antennas, but have not been used in wideband array antennas. The reason for limiting the use of such techniques is that, unlike narrowband arrays which require decoupling, wideband arrays require the ability to use coupling between cells to achieve wideband operation, with sparse methods, which can easily lead to performance degradation of the antenna. Moreover, after the array aperture is sparse, the sparse antenna units are irregularly distributed, and the array aperture is difficult to divide and use. The subarray-level phased array is only suitable for small-angle scanning, and the grating lobes are easy to appear when the scanning angle is increased, so that the current application is less. Disclosure of Invention The application provides a phased array radio frequency front end which can be used for solving the technical problem that an ultra-wideband array radio frequency channel is difficult to reduce. The phased array frequency radio frequency front end with low cost comprises an array antenna, a radio frequency link 1, a radio frequency link 2, a feed network, a frequency conversion module and a control module; the array antenna comprises m antenna units A and n antenna subarrays B, wherein each antenna subarray B comprises L antenna units A, the total of the array antenna is m+n.L antenna units, the aperture size of an antenna formed by the m antenna units A is SA, the aperture formed by the n antenna subarrays B is SB, and the working bandwidth of the array antenna is f1-f2; The antenna subarray B is connected with the radio frequency link 1, the antenna unit A is connected with the radio frequency link 2, the whole radio frequency front end is provided with n radio frequency links 1 and m radio frequency links 2 in total, the radio frequency link 1 and the radio frequency link 2 are connected with the feed network, the feed network is connected with the frequency conversion module, and the control module controls radio frequency switches in the radio frequency link 1 and the radio frequency link 2. The radio frequency link 1 comprises a 1-way L power divider, a T/R component 1, a filter 1 and a single-pole single-throw radio frequency switch, wherein the 1-way L power divider is connected with the T/R component 1, the T/R component 1 is connected with the filter 1, the filter 1 is connected with the single-pole single-throw radio frequency switch, and the working bandwidth of the T/R component 1 is f1-f3, wherein f3 is smaller than f2; The radio frequency link 2 comprises a single-pole double-throw radio frequency switch, a T/R component 2, a T/R component 3, a filter 1, a filter 2, two single-pole single-throw radio frequency switches and a 1-way power divider, wherein the single-pole double-throw radio frequency switch is connected with the T/R component 2 and the T/R component 3, the T/R component 2 is connected with the filter 1, the filter 1 is connected with one single-pole single-throw radio frequency switch, the T/R component 3 is connected with the filter 2, the filter 2 is connected with the other single-pole single-throw radio frequency switch, the two single-pole single-throw radio frequency switches are connected with the 1-way power divider, the working bandwidth of the T/R component 2 is f1-f3, and the working bandwidth of the T/R component 3 is f3-f2; The T/R assembly comprises a receiving and transmitting change-over switch, a power amplifier, an attenuator, a phase shifter and a low noise amplifier, and is used for realizing the functions of power amplification and amplitude phase adjustment in a receiving and transmitting state; The feed network is used for carrying out equal-amplitude and equal-phase distribution on radio frequency signals; the frequency conversion module comprises up-down conversion, wherein when the radio frequency front end transmits, an excitation signal is transmitted to the feed network after up-conversion, and is distributed by the feed network and then transmitted to the radio frequency link and the antenna