CN218217346U

CN218217346U - Radio frequency receiving module for satellite signal acquisition

Info

Publication number: CN218217346U
Application number: CN202221884060.0U
Authority: CN
Inventors: 周玉祥
Original assignee: Shiqiang Xianjin Shenzhen Technology Co ltd
Current assignee: Shiqiang Xianjin Shenzhen Technology Co ltd
Priority date: 2022-07-21
Filing date: 2022-07-21
Publication date: 2023-01-03
Anticipated expiration: 2032-07-21

Abstract

The utility model relates to a radio frequency receiving module for satellite signal gathers, include: the frequency conversion circuit comprises a radio frequency signal input end, an intermediate frequency signal output end, a preceding stage radio frequency path, a first frequency conversion path, a second frequency conversion path, a third frequency conversion path and an intermediate frequency path, wherein the preceding stage radio frequency path, the first frequency conversion path, the second frequency conversion path, the third frequency conversion path and the intermediate frequency path are sequentially connected in a cascade mode between the radio frequency signal input end and the intermediate frequency signal output end; the first frequency conversion path comprises a first single-pole-three-throw switch, a second single-pole-three-throw switch, a third branch, a fourth branch and a fifth branch; the public end of the first single-pole three-throw switch is connected with the preceding-stage radio frequency path, the third branch is connected with the first joint of the first single-pole three-throw switch and the first joint of the second single-pole three-throw switch, the fourth branch is connected with the second joint of the first single-pole three-throw switch and the second joint of the second single-pole three-throw switch, the fifth branch is connected with the third joint of the first single-pole three-throw switch and the third joint of the second single-pole three-throw switch, and the public end of the second single-pole three-throw switch is connected with the second frequency conversion path. Implement the utility model discloses can realize the receipt and the processing of wide band section signal.

Description

Radio frequency receiving module for satellite signal acquisition

Technical Field

The utility model relates to a radio frequency communication technical field, more specifically say, relate to a radio frequency receiving module for satellite signal gathers.

Background

Satellite communication uses frequency bands including L, S, C, ku, ka, etc., and the most commonly used frequency bands are C (4-8 GHz) and Ku (12-18 GHz), and the Ka (27-40 GHz) frequency band is the last line of sight. At present, the limited geosynchronous satellite orbit position above the earth equator is almost occupied by all countries, frequency resources in C and Ku frequency bands are largely used, the frequency working range of the Ka frequency band is several times larger, and the geosynchronous satellite orbit position has wide application prospect in modern military and civil communication. People need communicate through satellite signal just must carry out acquisition and processing to the signal, turns into lower intermediate frequency signal and baseband signal with the satellite signal of high frequency, just can carry out analysis and processing to the signal. In the conventional satellite signal acquisition and processing module, due to the design of a radio frequency channel, useless signals cannot be well separated in the acquisition and processing process of satellite signals, so that indexes such as signal-to-noise ratio and stray of the processed signals are not ideal.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in that, a radio frequency receiving module for satellite signal acquisition is provided.

The utility model provides a technical scheme that its technical problem adopted is: a radio frequency reception module for satellite signal acquisition is constructed, comprising: the frequency conversion device comprises a radio frequency signal input end, an intermediate frequency signal output end, a preceding stage radio frequency path, a first frequency conversion path, a second frequency conversion path, a third frequency conversion path and an intermediate frequency path, wherein the preceding stage radio frequency path, the first frequency conversion path, the second frequency conversion path, the third frequency conversion path and the intermediate frequency path are sequentially connected in a cascade mode between the radio frequency signal input end and the intermediate frequency signal output end;

the first frequency conversion channel comprises a first single-pole-three-throw switch, a second single-pole-three-throw switch, a third branch, a fourth branch and a fifth branch; the common end of the first single-pole-three-throw switch is connected with the pre-stage radio frequency path, the third branch is connected with a first joint of the first single-pole-three-throw switch and a first joint of the second single-pole-three-throw switch, the fourth branch is connected with a second joint of the first single-pole-three-throw switch and a second joint of the second single-pole-three-throw switch, the fifth branch is connected with a third joint of the first single-pole-three-throw switch and a third joint of the second single-pole-three-throw switch, and the public end of the second single-pole-three-throw switch is connected with the second frequency conversion path;

the third branch comprises a first filter and a first mixer, the input end of the first filter is connected with the first joint of the first single-pole three-throw switch, the output end of the first filter is connected with the first input end of the first mixer, the second input end of the first mixer is used for inputting a first local oscillation signal, and the output end of the first mixer is connected with the first joint of the second single-pole three-throw switch;

the fifth branch comprises a second filter and a second mixer, the input end of the second filter is connected with the third joint of the first single-pole three-throw switch, the output end of the second filter is connected with the first input end of the second mixer, the second input end of the second mixer is used for inputting a second local oscillation signal, and the output end of the second mixer is connected with the third joint of the second single-pole three-throw switch.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, preceding stage radio frequency route includes first branch road and the second branch road and the first single-pole double-throw switch and the second single-pole double-throw switch that the gain is different;

a common terminal of the first single-pole double-throw switch is connected with the radio-frequency signal input terminal, a first joint of the first single-pole double-throw switch is connected with a first end of the first branch, and a second joint of the first single-pole double-throw switch is connected with a first end of the second branch;

the common end of the second single-pole double-throw switch is connected with the common end of the first single-pole three-throw switch, the first joint of the second single-pole double-throw switch is connected with the second end of the first branch, and the second joint of the second single-pole double-throw switch is connected with the second end of the second branch.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal acquisition, the first branch includes the low noise and puts the module, the input of the low noise puts the first joint of module connection first single-pole double-throw switch, the output of module is put to the low noise connects the first joint of second single-pole double-throw switch; the second branch is a broadband straight-through link;

preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, the second frequency conversion route includes first radio frequency amplifier, second radio frequency amplifier, first adjustable numerical control attenuator, second adjustable numerical control attenuator, third mixer and third wave filter;

the input end of the first radio frequency amplifier is connected with the common end of the second single-pole three-throw switch, the output end of the first radio frequency amplifier is connected with the first end of the first adjustable numerical control attenuator, the second end of the first adjustable numerical control attenuator is connected with the first input end of the third mixer, the second input end of the third mixer is used for inputting a third local oscillation signal, the output end of the third mixer is connected with the first end of the third filter, the second end of the third filter is connected with the first end of the second adjustable numerical control attenuator, the second end of the second adjustable numerical control attenuator is connected with the input end of the second radio frequency amplifier, and the output end of the second radio frequency amplifier is connected with the third frequency conversion channel.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, the third frequency conversion route includes branching unit, sixth branch road and seventh branch road, the input of branching unit connects the second frequency conversion route, the first output of branching unit connects the sixth branch road, the second output of branching unit connects the seventh branch road; the sixth branch and the seventh branch are respectively used for connecting corresponding intermediate frequency paths.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, the sixth branch road includes: the first filter, the second mixer, the third filter, the fourth single-pole double-throw switch, the fourth filter, the fifth filter, the first intermediate frequency amplifier, the third single-pole double-throw switch, the sixth filter, the seventh filter and the fourth single-pole double-throw switch;

the first end of the fourth filter is connected with the first output end of the shunt, the second end of the fourth filter is connected with the first input end of the fourth mixer, the second input end of the fourth mixer is used for inputting a fourth local oscillation signal, the output end of the fourth mixer is connected with the first end of the fifth filter, the second end of the fifth filter is connected with the input end of the first intermediate frequency amplifier, the output end of the first intermediate frequency amplifier is connected with the common end of the third single-pole double-throw switch, the first joint of the third single-pole double-throw switch is connected with the first end of the sixth filter, the second end of the sixth filter is connected with the first joint of the third single-pole double-throw switch, and the common end of the third single-pole double-throw switch is connected with the intermediate frequency path.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, the seventh branch road includes: the first filter, the second mixer, the ninth filter, the second intermediate frequency amplifier, the fifth single-pole double-throw switch, the tenth filter, the eleventh filter and the sixth single-pole double-throw switch;

the first end of the eighth filter is connected to the second output end of the splitter, the second end of the eighth filter is connected to the first input end of the fifth mixer, the second input end of the fifth mixer is used for inputting a fifth local oscillator signal, the output end of the fifth mixer is connected to the first end of the ninth filter, the second end of the ninth filter is connected to the input end of the second intermediate frequency amplifier, the output end of the second intermediate frequency amplifier is connected to the common end of the fifth single-pole double-throw switch, the first joint of the fifth single-pole double-throw switch is connected to the first end of the tenth filter, the second end of the tenth filter is connected to the first joint of the sixth single-pole double-throw switch, and the common end of the sixth single-pole double-throw switch is connected to the intermediate frequency path.

Preferably, the utility model discloses a radio frequency receiving module for satellite signal gathers, the intermediate frequency route includes first intermediate frequency attenuator, third intermediate frequency amplifier, first change over switch, second change over switch, filter bank, fourth intermediate frequency amplifier, second intermediate frequency attenuator, AGC gain adjustment module and fifth intermediate frequency amplifier;

the first end of first intermediate frequency attenuator is connected the third frequency conversion route, the second end of first intermediate frequency attenuator is connected the input of third intermediate frequency amplifier, the output of third intermediate frequency amplifier is connected the common port of first change over switch, the first end of each wave filter corresponds the connection respectively in the filter bank the crossover sub of first change over switch, the second end of each wave filter corresponds the connection respectively in the filter bank the crossover sub of second change over switch, the common port of second change over switch is connected the input of fourth intermediate frequency amplifier, the first end of second intermediate frequency attenuator is connected to the output of fourth intermediate frequency amplifier, the second end of second intermediate frequency attenuator is connected the input of AGC gain adjustment module, the output of AGC gain adjustment module is connected the input of fifth intermediate frequency amplifier, the baseband acquisition card is connected to the output of fifth intermediate frequency amplifier.

Preferably, in the radio frequency receiving module for satellite signal acquisition of the present invention,

the conduction frequency of the first filter is 20MHz to 1000MHz;

and the conduction frequency of the second filter is 4000MHz to 6000MHz.

Preferably, the utility model discloses a in the radio frequency receiving module for satellite signal gathers, the model of first wave filter is QBF-20-1000-30, the model of second wave filter is QBF-4000-6000-40.

Implement the utility model discloses a radio frequency receiving module for satellite signal gathers has following beneficial effect: multiple indexes such as signal-to-noise ratio, acquisition precision, out-of-band rejection capability, channel isolation and the like in the radio frequency receiving process can be optimized.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

fig. 1 is a schematic diagram of a partial circuit of an embodiment of a radio frequency receiving module for satellite signal acquisition according to the present invention;

fig. 2 is a schematic diagram of a partial circuit of another embodiment of the rf receiving module for satellite signal acquisition according to the present invention.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 1 and fig. 2, in a first embodiment of a radio frequency receiving module for satellite signal acquisition of the present invention, the radio frequency receiving module includes: a radio frequency signal input end and an intermediate frequency signal output end, and a preceding stage radio frequency path 110, a first frequency conversion path 120, a second frequency conversion path 130, a third frequency conversion path 140 and an intermediate frequency path 150 which are connected in series between the radio frequency signal input end and the intermediate frequency signal output end; the first frequency conversion path 120 includes a first single-pole-three-throw switch 121, a second single-pole-three-throw switch 122, a third branch 123, a fourth branch 124 and a fifth branch 125; the common end of the first single-pole-three-throw switch 121 is connected with the pre-stage radio frequency path 110, the third branch 123 is connected with the first joint of the first single-pole-three-throw switch 121 and the first joint of the second single-pole-three-throw switch 122, the fourth branch 124 is connected with the second joint of the first single-pole-three-throw switch 121 and the second joint of the second single-pole-three-throw switch 122, the fifth branch 125 is connected with the third joint of the first single-pole-three-throw switch 121 and the third joint of the second single-pole-three-throw switch 122, and the public end of the second single-pole-three-throw switch 122 is connected with the second frequency conversion path 130; the third branch 123 includes a first filter 1231 and a first mixer 1232, an input end of the first filter 1231 is connected to the first junction of the first single-pole-three-throw switch 121, an output end of the first filter 1231 is connected to a first input end of the first mixer 1232, a second input end of the first mixer 1232 is used for inputting a first local oscillator signal 1233, and an output end of the first mixer 1232 is connected to the first junction of the second single-pole-three-throw switch 122; the fourth branch 124 comprises a second filter, a first end of the second filter is connected to the second terminal of the first single-pole-three-throw switch 121, and a second end of the second filter is connected to the second terminal of the second single-pole-three-throw switch 122; the fifth branch 125 includes a second filter 1251 and a second mixer 1252, an input terminal of the second filter 1251 is connected to the third terminal of the first single-pole-three-throw switch 121, an output terminal of the second filter 1251 is connected to a first input terminal of the second mixer 1252, a second input terminal of the second mixer 1252 is used for inputting the second local oscillator signal 1253, and an output terminal of the second mixer 1252 is connected to the third terminal of the second single-pole-three-throw switch 122. In particular, the reception of satellite signals by means of an antenna may also be understood as primary radio frequency signals. The primary radio frequency signal is input through a radio frequency signal input end, and after the primary radio frequency signal is subjected to primary processing sequentially through a preceding stage device channel, a first stage radio frequency signal is obtained through first stage frequency conversion of a first frequency conversion channel 120, the first stage radio frequency signal is subjected to frequency conversion processing of a second frequency conversion channel 130 to obtain a second stage radio frequency signal, the second stage radio frequency signal is subjected to processing of a third frequency conversion channel 140 to finally obtain a signal of a target frequency, namely an intermediate frequency signal, and the intermediate frequency signal is subjected to processing of an intermediate frequency channel 150 to obtain a final intermediate frequency signal and is output to a baseband acquisition card for demodulation processing. In the first frequency conversion path 120, the input primary rf signal is selected through the first single-pole-three-throw switch 121. When the single-pole double-throw switch 111 is used for receiving a satellite signal in a first frequency range, the first frequency conversion path 120 is switched to the third branch 123 through the first single-pole double-throw switch 111, and a frequency band signal is filtered through the first filter 1231 arranged in the third branch 123. Wherein the first frequency range is frequency signals below 1000 MHz. The filtered satellite signal is mixed by the first mixer 1232 to obtain a target frequency range, i.e. a corresponding first-stage rf signal, and the rf signal of the third branch 123 is switched by the second single-pole-three-throw switch 122 and input to the second frequency conversion path 130. The frequency range of the first local oscillator signal 1233 input by the first mixer 1232 is 2150MHz-2600MHz. For receiving the satellite signal in the second frequency range, the first frequency conversion path 120 is switched to the fourth branch 124 through the first single-pole double-throw switch 111, wherein the fourth branch 124 is a through branch. That is, the input primary rf signal is directly input to the second frequency conversion path 130 through the second single-pole-three-throw switch 122 without being subjected to frequency conversion. Wherein the second frequency range refers to signals in the range of 1000MHz to 4000 MHz. When the frequency converter is used for receiving a satellite signal in a third frequency range, the first frequency conversion path 120 is switched to the fifth branch 125 through the first single-pole double-throw switch 111, and the frequency band signal is filtered through the second filter 1251 disposed in the fifth branch 125, where the third frequency range refers to a frequency higher than 4000 MHz. The filtered satellite signal is mixed by the second mixer 1252 to obtain a target frequency range, that is, a corresponding first-stage radio frequency signal, and the radio frequency signal of the fifth branch 125 is switched by the second single-pole-triple-throw switch 122 to be input to the second frequency conversion path 130. The frequency of the second local oscillation signal 1253 input by the second mixer 1252 is 2550Hz to 2900MHz. Different first-stage frequency conversion or no first-stage frequency conversion is carried out on different satellite signals, and finally, a signal in a preset frequency range is obtained to be subjected to second-stage frequency conversion, so that the radio frequency signal range of the radio frequency receiving module is enlarged.

Optionally, on the basis of the above, in the radio frequency receiving module for satellite signal acquisition of the present invention, the on-frequency of the first filter 1231 is 20MHz to 1000MHz; the on frequency of the second filter 1251 is 4000MHz to 6000MHz. In one embodiment, the first filter 1231 is of type QBF-20-1000-30 and the second filter 1251 is of type QBF-4000-6000-40. An ideal filter should have a completely flat passband, and outside the passband all frequencies should be completely attenuated, and the conversion should be done over a very small frequency range; in general, the design of the filter tries to ensure that the narrower the roll-off range, the better, so that the performance of the filter is closer to the design. The maximum frequency of the QBF series filter can reach 170GHz; therefore, the QBF-20-1000-30 is selected as the first filter, the stop band rejection is 30dB, the insertion loss is 1.3, and the standing wave is 1.3. The second filter adopts QBF-4000-6000-40, the stop band is restrained to 40dB, the insertion loss is 1.3, and the standing wave is 1.3.

Optionally, the front stage rf path 110 includes a first branch 113 and a second branch 114 with different gains, and a first single-pole double-throw switch 111 and a second single-pole double-throw switch 112; a common terminal of the first single-pole double-throw switch 111 is connected with a radio-frequency signal input terminal, a first joint of the first single-pole double-throw switch 111 is connected with a first terminal of a first branch 113, and a second joint of the first single-pole double-throw switch 111 is connected with a first terminal of a second branch 114; the common terminal of the second single-pole double-throw switch 112 is connected with the common terminal of the first single-pole three-throw switch 121, the first joint of the second single-pole double-throw switch 112 is connected with the second terminal of the first branch 113, and the second joint of the second single-pole double-throw switch 112 is connected with the second terminal of the second branch 114. The first branch 113 and the second branch 114 have different gains, and when the received signal level is high, the first spdt switch 111 and the second spdt switch 112 may be switched to operate the front stage rf path 110 in the branch with lower gain. When the received signal level is low to a certain extent, the front stage rf path 110 can be operated in the branch with higher gain by switching the first single-pole double-throw switch 111 and the second single-pole double-throw switch 112. The primary radio frequency signal is amplified through the high-gain branch.

Optionally, the first branch 113 includes a low-noise amplifier module 1131, an input end of the low-noise amplifier module 1131 is connected to the first terminal of the first single-pole double-throw switch 111, and an output end of the low-noise amplifier module 1131 is connected to the first terminal of the second single-pole double-throw switch 112; the second branch 114 is a broadband through link; specifically, in the first branch 113, the primary amplification of the small signal is performed by providing a low noise amplifier. The low noise amplifier can be constructed by adopting a TSY-172+ chip and peripheral circuits thereof. The other branch is a broadband through link which does not amplify the input signal.

Optionally, the second frequency conversion path 130 includes a first radio frequency amplifier 131, a second radio frequency amplifier 137, a first adjustable digitally controlled attenuator 132, a second adjustable digitally controlled attenuator 136, a third mixer 133, and a third filter; the input end of the first radio frequency amplifier 131 is connected to the common end of the second single-pole-three-throw switch 122, the output end of the first radio frequency amplifier 131 is connected to the first end of the first adjustable digital controlled attenuator 132, the second end of the first adjustable digital controlled attenuator 132 is connected to the first input end of the third mixer 133, the second input end of the third mixer 133 is used for inputting the third local oscillator signal 134, the output end of the third mixer 133 is connected to the first end of the third filter 135, the second end of the third filter 135 is connected to the first end of the second adjustable digital controlled attenuator 136, the second end of the second adjustable digital controlled attenuator 136 is connected to the input end of the second radio frequency amplifier 137, and the output end of the second radio frequency amplifier 137 is connected to the third frequency conversion path 140. Specifically, the second frequency conversion path 130 performs a second frequency conversion on the first-stage rf signal output by the first frequency conversion path 120, and the first-stage rf signal is amplified by the first rf amplifier 131 in the first frequency conversion path 120, and the first adjustable digitally controlled attenuator 132 controls and adjusts the magnitude of the signal entering the second mixer 1252. After the output signal of the second mixer 1252 is filtered by the third filter 135, the gain of the output signal is controlled by the second adjustable digitally controlled attenuator 136, and the radio frequency signal is amplified by the second radio frequency amplifier 137, so as to finally obtain a second stage radio frequency signal and output the second stage radio frequency signal to the third frequency conversion path 140. The frequency range of the third local oscillator signal 134 is 550MHz to 2560MHz.

Optionally, the third frequency conversion path 140 includes a splitter 141, a sixth branch 142 and a seventh branch 143, an input end of the splitter 141 is connected to the second frequency conversion path 130, a first output end of the splitter 141 is connected to the sixth branch 142, and a second output end of the splitter 141 is connected to the seventh branch 143; the sixth branch 142 and the seventh branch 143 are respectively used for connecting to the corresponding if paths 150. Specifically, in the third frequency conversion path 140, a sixth branch 142 and a seventh branch 143 are arranged to respectively perform three-time frequency conversion on the second-stage radio frequency signal output by the second frequency conversion path 130 to obtain an intermediate frequency signal. Wherein the sixth branch 142 and the seventh branch 143 are intermediate frequency signals with different frequencies, respectively. In one embodiment, the sixth branch 142 is used to obtain an intermediate frequency signal of 140MHz, and the seventh branch 143 is used to obtain an intermediate frequency signal of 70 MHz.

Optionally, the sixth branch 142 includes: a fourth filter 1421, a fourth mixer 1422, a fifth filter 1424, a first intermediate frequency amplifier 1425, a third single-pole double-throw switch 1426, a sixth filter 1427, a seventh filter 1428, and a fourth single-pole double-throw switch 1429; a first end of the fourth filter 1421 is connected to the first output end of the splitter 141, a second end of the fourth filter 1421 is connected to a first input end of the fourth mixer 1422, a second input end of the fourth mixer 1422 is used for inputting a fourth local oscillator signal 1423, an output end of the fourth mixer 1422 is connected to a first end of the fifth filter 1424, a second end of the fifth filter 1424 is connected to an input end of the first intermediate frequency amplifier 1425, an output end of the first intermediate frequency amplifier 1425 is connected to a common terminal of the third single-pole double-throw switch 1426, a first terminal of the third single-pole double-throw switch 1426 is connected to a first end of the sixth filter 1427, a second end of the sixth filter 1427 is connected to a first terminal of the third single-pole double-throw switch 1426, and a common terminal of the third single-pole double-throw switch 1426 is connected to the intermediate frequency path 150. Specifically, in the sixth branch 142, the input second-stage radio frequency signal is filtered by a fourth filter 1421, and the second-stage radio frequency signal is mixed by a fourth mixer 1422, where the frequency of the fourth local oscillator signal 1423 is 1090MHz to 1085MHz. The intermediate frequency signal of 140MHz is finally obtained by the mixing of the fourth mixer 1422, and is filtered and conditioned by the fifth filter 1424 and then amplified by the first intermediate frequency amplifier 1425. The path is switched to the sixth filter 1427 or the seventh filter 1428 according to the intermediate frequency of the bandwidth of the intermediate frequency signal, so as to implement further processing of the signal, so as to improve the indexes such as the signal-to-noise ratio and the spurious signals. Wherein the sixth filter 1427 or the seventh filter 1428 is a filter with different turn-on frequencies. The on-frequency of the fourth filter 1421 is 1GHz to 2GHz, the on-frequency of the fifth filter 1424 is 130MHz to 150MHz, the on-frequency of the sixth filter 1427 is 135MHz to 140MHz, and the on-frequency of the seventh filter 1428 is 140MHz to 145MHz.

Optionally, the seventh branch 143 includes: an eighth filter 1431, a fifth mixer 1432, a ninth filter 1434, a second intermediate frequency amplifier 1435, a fifth single-pole double-throw switch 1436, a tenth filter 1437, an eleventh filter 1438, and a sixth single-pole double-throw switch 1439; a first terminal of the eighth filter 1431 is connected to the second output terminal of the splitter 141, a second terminal of the eighth filter 1431 is connected to a first input terminal of the fifth mixer 1432, a second input terminal of the fifth mixer 1432 is used for inputting a fifth local oscillator signal 1433, an output terminal of the fifth mixer 1432 is connected to a first terminal of the ninth filter 1434, a second terminal of the ninth filter 1434 is connected to an input terminal of the second intermediate frequency amplifier 1435, an output terminal of the second intermediate frequency amplifier 1435 is connected to a common terminal of the fifth single-pole double-throw switch 1436, a first terminal of the fifth single-pole double-throw switch 1436 is connected to a first terminal of the tenth filter 1437, a second terminal of the tenth filter 1437 is connected to a first terminal of the sixth single-pole double-throw switch 1439, and the common terminal of the sixth single-pole double-throw switch 1439 is connected to the intermediate frequency path 150. Specifically, in the seventh branch 143, the input second-stage radio frequency signal is filtered by an eighth filter 1431, and the second-stage radio frequency signal is mixed by a fifth mixer 1432, where the frequency of the fifth local oscillator signal 1433 is 1076MHz to 1176MHz, an intermediate frequency signal of 70MHz is finally obtained through the mixing by the fifth mixer 1432, the intermediate frequency signal is amplified by a second intermediate frequency amplifier 1435 after being filtered and conditioned by a ninth filter 1434, and a path is switched to a tenth filter 1437 or an eleventh filter 1438 according to the intermediate frequency of the bandwidth of the intermediate frequency signal, so as to implement further processing of the signal, so as to improve indexes such as signal-to-noise ratio and spurious signals. Where the tenth filter 1437 or the eleventh filter 1438 are filters having different on-bands. The on-frequency of the eighth filter 1431 is 1GHz to 2GHz, the on-frequency of the ninth filter 1432 is 60MHz to 80MHz, the on-frequency of the tenth filter 1437 is 65MHz to 70MHz, and the on-frequency of the eleventh filter 1438 is 70MHz to 75MHz.

Optionally, as shown in fig. 2, the if path 150 includes a first if attenuator 151, a third if amplifier 152, a first switch 153, a second switch 154, a filter bank 155, a fourth if amplifier 156, a second if attenuator 157, an AGC gain adjustment module 158, and a fifth if amplifier 159; the first end of the first intermediate frequency attenuator 151 is connected to the third frequency conversion path 140, the second end of the first intermediate frequency attenuator 151 is connected to the input end of the third intermediate frequency amplifier 152, the output end of the third intermediate frequency amplifier 152 is connected to the common end of the first switch 153, the first ends of the filters in the filter bank 155 are respectively and correspondingly connected to the switch joints of the first switch 153, the second ends of the filters in the filter bank 155 are respectively and correspondingly connected to the switch joints of the second switch 154, the common end of the second switch 154 is connected to the input end of the fourth intermediate frequency amplifier 156, the output end of the fourth intermediate frequency amplifier 156 is connected to the first end of the second intermediate frequency attenuator 157, the second end of the second intermediate frequency attenuator 157 is connected to the input end of the AGC gain adjustment module 158, the output end of the AGC gain adjustment module 158 is connected to the input end of the fifth intermediate frequency amplifier 159, and the output end of the fifth intermediate frequency amplifier 159 is connected to the baseband intermediate frequency acquisition card. Specifically, the obtained intermediate frequency signals of 70MHz or 140MHz can be conditioned separately through the intermediate frequency path 150, wherein the gain control is performed on the input intermediate frequency signals through the first intermediate frequency attenuator 151 and the gain control is performed through the third intermediate frequency amplifier 152 in synchronization with the amplification. The intermediate frequency signal after gain control is conditioned and filtered by the filter bank 155, wherein the filter bank 155 includes various filters with different on frequencies, and the intermediate frequency signal is divided and filtered again according to the intermediate frequency of the signal bandwidth. The filters in the filter bank 155 can be switched by a three-throw or more-pin switch, and the main purpose is to divide the frequency band into smaller frequency bands, reduce the frequency bandwidth, facilitate signal processing and filtering, and make the signal processing index better. The filtered intermediate frequency signal is subjected to gain control again through the fourth intermediate frequency amplifier 156 and the second intermediate frequency attenuator 157, and meanwhile, adjustable gain control is performed through the AGC gain adjusting module 158, and the AGC gain adjusting module 158 may adopt a PUT5674 module, and specifically, may also adopt an AD603 and a single chip microcomputer and other devices to build up.

It is to be understood that the foregoing examples merely represent preferred embodiments of the present invention, and that the description thereof is more specific and detailed, but not intended to limit the scope of the invention; it should be noted that, for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention; therefore, all changes and modifications that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A radio frequency receive module for satellite signal acquisition, comprising: the frequency conversion circuit comprises a radio frequency signal input end, an intermediate frequency signal output end, a preceding stage radio frequency path, a first frequency conversion path, a second frequency conversion path, a third frequency conversion path and an intermediate frequency path, wherein the preceding stage radio frequency path, the first frequency conversion path, the second frequency conversion path, the third frequency conversion path and the intermediate frequency path are sequentially connected in a cascade mode between the radio frequency signal input end and the intermediate frequency signal output end;

the fifth branch circuit comprises a second filter and a second mixer, wherein the input end of the second filter is connected with the third joint of the first single-pole three-throw switch, the output end of the second filter is connected with the first input end of the second mixer, the second input end of the second mixer is used for inputting a second local oscillator signal, and the output end of the second mixer is connected with the third joint of the second single-pole three-throw switch.

2. The rf receive module of claim 1, wherein the pre-stage rf path comprises first and second branches with different gains and first and second single-pole double-throw switches;

3. The radio frequency receiving module for satellite signal acquisition of claim 2,

the first branch comprises a low-noise amplifier module, the input end of the low-noise amplifier module is connected with the first joint of the first single-pole double-throw switch, and the output end of the low-noise amplifier module is connected with the first joint of the second single-pole double-throw switch; the second branch is a broadband direct link.

4. The radio frequency reception module for satellite signal acquisition of claim 2, wherein the second frequency conversion path comprises a first radio frequency amplifier, a second radio frequency amplifier, a first adjustable digitally controlled attenuator, a second adjustable digitally controlled attenuator, a third mixer, and a third filter;

5. The rf receiving module of claim 1, wherein the third frequency conversion path comprises a splitter, a sixth branch and a seventh branch, an input of the splitter is connected to the second frequency conversion path, a first output of the splitter is connected to the sixth branch, and a second output of the splitter is connected to the seventh branch; and the sixth branch and the seventh branch are respectively used for connecting corresponding intermediate frequency paths.

6. The radio frequency reception module for satellite signal acquisition of claim 5, wherein the sixth branch comprises: the first filter, the second mixer, the third filter, the fourth single-pole double-throw switch, the fourth filter, the fifth filter, the first intermediate frequency amplifier, the third single-pole double-throw switch, the sixth filter, the seventh filter and the fourth single-pole double-throw switch;

7. The radio frequency reception module for satellite signal acquisition of claim 5, wherein the seventh branch comprises: the first filter, the second mixer, the ninth filter, the second intermediate frequency amplifier, the fifth single-pole double-throw switch, the tenth filter, the eleventh filter and the sixth single-pole double-throw switch;

the first end of the eighth filter is connected to the second output end of the splitter, the second end of the eighth filter is connected to the first input end of the fifth mixer, the second input end of the fifth mixer is used for inputting a fifth local oscillation signal, the output end of the fifth mixer is connected to the first end of the ninth filter, the second end of the ninth filter is connected to the input end of the second intermediate frequency amplifier, the output end of the second intermediate frequency amplifier is connected to the common end of the fifth single-pole double-throw switch, the first joint of the fifth single-pole double-throw switch is connected to the first end of the tenth filter, the second end of the tenth filter is connected to the first joint of the sixth single-pole double-throw switch, and the common end of the sixth single-pole double-throw switch is connected to the intermediate frequency path.

8. The RF receiving module for satellite signal acquisition of claim 5, wherein the IF path includes a first IF attenuator, a third IF amplifier, a first switch, a second switch, a filter bank, a fourth IF amplifier, a second IF attenuator, an AGC gain adjustment module, and a fifth IF amplifier;

9. The radio frequency reception module for satellite signal acquisition of claim 1,

the conduction frequency of the first filter is 20MHz to 1000MHz;

and the conduction frequency of the second filter is 4000MHz to 6000MHz.

10. The radio frequency reception module for satellite signal acquisition of claim 9,

the model of the first filter is QBF-20-1000-30, and the model of the second filter is QBF-4000-6000-40.