CN113258883B - Device and method for extracting weak signal and suppressing strong interference signal - Google Patents
Device and method for extracting weak signal and suppressing strong interference signal Download PDFInfo
- Publication number
- CN113258883B CN113258883B CN202110641276.8A CN202110641276A CN113258883B CN 113258883 B CN113258883 B CN 113258883B CN 202110641276 A CN202110641276 A CN 202110641276A CN 113258883 B CN113258883 B CN 113258883B
- Authority
- CN
- China
- Prior art keywords
- low
- pass filter
- noise amplifier
- signals
- stage circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/26—Modifications of amplifiers to reduce influence of noise generated by amplifying elements
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/68—Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Amplifiers (AREA)
Abstract
The invention provides a device and a method for extracting weak signals and inhibiting strong interference signals, wherein the device comprises a first-stage circuit and at least one second-stage circuit which are sequentially connected; the first-stage circuit comprises a duplexer, a first low-noise amplifier and a load resistor, the duplexer comprises a first low-pass filter and a high-pass filter, the input ends of the first low-pass filter and the high-pass filter are input ports of the device, the input end of the first low-noise amplifier is connected with the output end of the first low-pass filter, one end of the load resistor is connected with the output end of the high-pass filter, and the other end of the load resistor is grounded; the second-stage circuit comprises a second low-pass filter and a second low-noise amplifier, and the output end of the second low-pass filter is connected with the input end of the second low-noise amplifier. The method realizes extraction of useful weak signals of a DC-800 MHz frequency band, amplifies the useful signals from-67 dBm to about-7 dBm, deeply inhibits strong interference signals of 1.25GHz, has the inhibition degree of more than 140dBc, improves the electromagnetic compatibility and prevents the interference signals from radiating to the whole circuit space.
Description
Technical Field
The present invention relates to communication technologies, and in particular, to an apparatus and method for extracting weak signals and suppressing strong interference signals.
Background
In a communication receiving system, the extraction of a useful signal and the suppression of an interference signal are key to guarantee the communication quality. Particularly, when the desired signal strength is weak and the interference signal strength is strong, for example, the desired signal strength of a certain communication receiving system is-67 dBm, the interference signal strength is 10dBm, and the power strengths thereof differ by 5 × 107And the extraction capability of the useful signal and the suppression degree of the interference signal are improved.
The useful signal is generally a low frequency component, while the interfering signal is generally a high frequency component or higher harmonics. In general, a cascade of a plurality of low-pass filters is used to extract a useful signal and suppress an interference signal from such a mixed signal, and the useful signal and the interference signal are extracted and suppressed by the cascade of the low-pass filters.
Since the power strength of the interference signal is much larger than that of the useful signal, to achieve deep suppression of such strong interference signal, a cascade of a plurality of low-pass filters is needed, and a single low-pass filter cannot provide such high suppression degree. The cascade connection of the low-pass filter brings the device volume increase, and the process and the cost are increased, which is contrary to the miniaturization trend of the device, the process quality control and the commercial cost control target. More importantly, the low-pass filter is used for setting a low-frequency signal through the index of the filter, in the low-pass filter, the high-frequency signal is equivalent to a short circuit, the energy consumed on the filter is little, and most of the high-frequency signal is reflected back to a signal source; if the strength of a plurality of interference signals is too large, the source load can be damaged, and in addition, space radiation can be formed, and the electromagnetic compatibility characteristic of the whole receiving system is influenced.
Disclosure of Invention
In order to solve the above-mentioned related prior art deficiencies, the present invention provides a device and a method for extracting weak signals and suppressing strong interference signals, which utilize a duplexer to separate useful low-frequency signals and interference high-frequency signals, and absorb high-frequency signals through a load, thereby realizing extraction of useful weak signals in a DC-800 MHz frequency band while reducing the order of a low-pass filter and the size of the device, amplifying useful signals from-67 dBm to about-7 dBm, and simultaneously deeply suppressing strong interference signals of 1.25GHz, the suppression degree is greater than 140dBc, the electromagnetic compatibility is improved, and interference signals are prevented from radiating to the whole circuit space.
In order to realize the purpose of the invention, the following scheme is adopted:
a device for extracting weak signals and suppressing strong interference signals comprises a first-stage circuit and at least one second-stage circuit which are sequentially connected;
the first-stage circuit comprises a duplexer, a first low-noise amplifier and a load resistor, the duplexer comprises a first low-pass filter and a high-pass filter, the input ends of the first low-pass filter and the high-pass filter are input ports of the device, the input end of the first low-noise amplifier is connected with the output end of the first low-pass filter, one end of the load resistor is connected with the output end of the high-pass filter, and the other end of the load resistor is grounded;
the second-stage circuit comprises a second low-pass filter and a second low-noise amplifier, and the output end of the second low-pass filter is connected with the input end of the second low-noise amplifier;
when one second-stage circuit is available, the output end of the first low-noise amplifier is connected with the input end of the second low-pass filter, and the output end of the second low-noise amplifier is the output port of the device;
when the number of the second-stage circuits is multiple, the output end of the first low-noise amplifier is connected with the input end of the second low-pass filter of the first second-stage circuit, the output end of the second low-noise amplifier of the previous second-stage circuit is connected with the input end of the second low-pass filter of the next second-stage circuit, and the output end of the second low-noise amplifier of the last second-stage circuit is the output port of the device.
Further, the high-pass filter is used for filtering the signal entering the duplexer from the input port so as to prevent the low-frequency useful signal and pass the high-frequency interference signal;
the load resistor is used for absorbing the high-frequency interference signal passing through the high-pass filter;
the first low-pass filter is used for filtering the signal entering the duplexer from the input port so as to prevent a high-frequency interference signal and pass a low-frequency useful signal;
the first low-noise amplifier is used for carrying out primary amplification on the low-frequency useful signal passing through the first low-pass filter and then transmitting the low-frequency useful signal to the second-stage circuit;
the second low-pass filter is used for further filtering the amplified signal input into the second-stage circuit;
the second low noise amplifier is used for carrying out secondary amplification on the signal filtered by the second low pass filter.
Furthermore, two second-stage circuits are provided, including a second-stage circuit I and a second-stage circuit II;
the second-stage circuit I comprises a second low-pass filter I and a second low-noise amplifier I, and the output end of the second low-pass filter I is connected with the input end of the second low-noise amplifier I;
the second-stage circuit II comprises a second low-pass filter II and a second low-noise amplifier II, and the output end of the second low-pass filter II is connected with the input end of the second low-noise amplifier II;
the output end of the first low-noise amplifier is connected with the input end of the second low-pass filter I, the output end of the second low-noise amplifier I is connected with the input end of the second low-pass filter II, and the output end of the second low-noise amplifier II is an output port of the device.
Further, the device still includes the cavity, and the cavity separates for 3 cavities through 2 metal baffle: a first chamber, a second chamber, a third chamber; the first-stage circuit is arranged in the first cavity, the second-stage circuit I is arranged in the second cavity adjacent to the first cavity, and the second-stage circuit II is arranged in the third cavity adjacent to the second cavity.
Further, one end of the cavity is provided with an input port which is used as an input port of the device, the input port is communicated to the first cavity, and the input end of the duplexer is connected with the input port through a microstrip line;
the other end of the cavity is provided with an output port which is used as an output port of the device, the output port is communicated to the third cavity, and the output end of the second low-noise amplifier II is connected with the output port through a microstrip line;
the output end of the first low-pass filter is connected with a first low-noise amplifier through a microstrip line;
the output end of the high-pass filter is connected with a load resistor through a microstrip line;
the output end of the first low-noise amplifier penetrates through the corresponding metal partition plate through a microstrip line to extend out of the second cavity and is connected with the input end of the second low-pass filter I;
the output end of the second low-pass filter I is connected with a second low-noise amplifier I through a microstrip line;
the output end of the second low-noise amplifier I penetrates through the corresponding metal partition plate through a microstrip line to extend out of the third chamber and is connected with the input end of the second low-pass filter II;
the output end of the second low-pass filter II is connected with a second low-noise amplifier II through a microstrip line.
Further, be equipped with the dielectric-slab in the cavity, metal baffle is located the dielectric-slab openly, and the cavity top is equipped with the metal lid, and metal lid, dielectric-slab openly, metal baffle form first cavity, second cavity, third cavity jointly, and first order circuit, second level circuit I, second level circuit II all locate the dielectric-slab openly.
Furthermore, the back of the dielectric plate is provided with a power supply circuit, the power supply circuit is connected with a power supply port, the power supply port is arranged on the side wall of the cavity, the dielectric plate is provided with a first power supply through hole positioned in the first cavity, a second power supply through hole positioned in the second cavity and a third power supply through hole positioned in the third cavity, the first-stage circuit is connected with the power supply circuit through the first power supply through hole, the second-stage circuit I is connected with the power supply circuit through the second power supply through hole, and the second-stage circuit II is connected with the power supply circuit through the third power supply through hole.
Furthermore, clamping grooves are formed in two side walls of the cavity, the metal partition plate is arranged in the clamping grooves, a groove is formed in the inner bottom surface of the metal cover, and the groove is matched with the top of the metal partition plate.
A method for extracting weak signals and suppressing strong interference signals is carried out by adopting a device for extracting the weak signals and suppressing the strong interference signals, and comprises the following steps:
a high-pass filter of the duplexer filters a signal entering the duplexer from the input port, prevents a low-frequency useful signal from passing through a high-frequency interference signal, and a load resistor absorbs the high-frequency interference signal passing through the high-pass filter;
a first low-pass filter of the duplexer filters a signal entering the duplexer from the input port, prevents a high-frequency interference signal from passing through a low-frequency useful signal, and a first low-noise amplifier performs primary amplification on the low-frequency useful signal passing through the first low-pass filter and then transmits the low-frequency useful signal to a second low-pass filter I of a second-stage circuit I;
the second low-pass filter I filters the signals amplified in the first stage again, after high-frequency interference signals amplified by the first low-noise amplifier are removed, the signals are input to the second low-noise amplifier I, and the second low-noise amplifier I amplifies the signals in the second stage and then transmits the amplified signals to the second low-pass filter II of the second-stage circuit II;
the second low-pass filter II is used for filtering the signals amplified in the second stage again, further removing high-frequency interference signals amplified by the second low-noise amplifier I, inputting the signals to the second low-noise amplifier II, and outputting the signals from an output port after the signals are amplified in the third stage by the second low-noise amplifier II;
finally, a low-frequency useful signal is obtained from the output port, and a high-frequency interference signal is absorbed at the load resistor and is suppressed in the second low-pass filter I and the second low-pass filter II.
The signals entering the duplexer from the input port comprise low-frequency useful signals, low-noise signals above 800MHz, 1.2GHz interference signals with power intensity of 10dBm and higher harmonics; the high-pass filter is used for realizing a passband above 1.2GHz, and the rejection degree of 800MHz is-50 dB; the first low-pass filter, the second low-pass filter I and the second low-pass filter II are all used for realizing a pass band below 800MHz, and the suppression degree of 1.25GHz is-40 dB; the frequency ranges of the first low noise amplifier, the second low noise amplifier I and the second low noise amplifier II are all DC-200 MHz, the typical value of the noise coefficient in the working frequency band is 1.8dB, and the gain is 23 dB.
The invention has the beneficial effects that:
1. the duplexer is used for separating a useful low-frequency signal and an interference high-frequency signal, the high-frequency signal is absorbed through a load, and the interference signal entering a subsequent circuit is greatly reduced, so that the order of a low-pass filter and the size of a device are effectively reduced, a useful weak signal of a first low-pass filter in the duplexer is subjected to first-stage amplification through a first low-noise amplifier, and the strength of the useful signal is improved; the first-stage low-noise amplifier can also amplify interference high-frequency signals which possibly enter the circuit, the strength of useful weak signals amplified by the first stage is still very low, the signals amplified by the first stage use a second low-pass filter I to filter the interference high-frequency signals which possibly enter the circuit, and then the second low-noise amplifier I performs second-stage amplification; similarly, the signal after the second-stage amplification uses a second low-pass filter II to filter out interference high-frequency signals which may enter the circuit, and then the interference high-frequency signals are output after the third-stage amplification is carried out by a second low-noise amplifier II; the method has the advantages that the useful weak signals of the DC-800 MHz frequency band are extracted integrally, the useful signals are amplified to about-7 dBm from-67 dBm, meanwhile, the strong interference signals of 1.25GHz are deeply inhibited, and the inhibition degree is more than 140 dBc;
2. the structure of the cavity is adopted, and the metal partition plates are arranged between each stage of circuits to form a plurality of independent cavities for respectively accommodating each circuit, interference signals entering the second stage circuit I are greatly reduced due to the sorting and absorption of the interference signals by the first stage circuit, and the interference signals entering the second stage circuit II are smaller after passing through the low-pass filtering and amplifying circuit of the second stage circuit I, so that the influence of the interference signals on output signals is minimized, and the electromagnetic compatibility is improved;
3. the filter amplifying circuits and the power supply circuits are respectively arranged on the front side and the back side of the dielectric plate, mutual interference is reduced, microstrip lines connected between the filter amplifying circuits of each stage are connected at the metal parting strips through openings, and the distance between the edge of each opening and the microstrip line is as small as possible, so that interference signals are not leaked at the openings to the next stage of circuit.
Drawings
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Fig. 1 is a schematic circuit diagram according to an embodiment of the present application.
Fig. 2 is a schematic diagram of an output result according to an embodiment of the present application.
Fig. 3 is a top view of a solid structure according to an embodiment of the present disclosure.
Fig. 4 is a bottom view of the physical structure of the embodiment of the present application.
FIG. 5 is a side cross-sectional view of a solid structure in accordance with an embodiment of the present application.
Reference numerals:
the power supply circuit comprises a duplexer-11, a high-pass filter-F1, a first low-pass filter-F2, a first low-noise amplifier-11 a, a load resistor-11 b, a second low-pass filter I-12, a second low-noise amplifier I-12a, a second low-pass filter II-13, a second low-noise amplifier II-13a, a first power supply through hole-21, a second power supply through hole-22, a third power supply through hole-23, a power supply circuit-24, a power supply port-25, a cavity-3, an input port-31, an output port-32, a metal partition-33, a dielectric plate-34, a metal cover-35, a first cavity-301, a second cavity-302, a third cavity-303 and a microstrip line-4.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings, but the described embodiments of the present invention are a part of the embodiments of the present invention, not all of the embodiments of the present invention.
The embodiment of the application provides a device for extracting weak signals and inhibiting strong interference signals, which comprises a first-stage circuit and two second-stage circuits which are sequentially connected. The two second-stage circuits are a second-stage circuit I and a second-stage circuit II.
As shown in fig. 1, the first stage circuit includes a duplexer 11, a first low-noise amplifier 11a, and a load resistor 11b, the duplexer 11 includes a first low-pass filter F2 and a high-pass filter F1, the input terminals of the first low-pass filter F2 and the high-pass filter F1 are the input ports of the apparatus, the input terminal of the first low-noise amplifier 11a is connected to the output terminal of the first low-pass filter F2, and one end of the load resistor 11b is connected to the output terminal of the high-pass filter F1, and the other end is grounded.
Wherein, the high-pass filter F1 is used to filter the signal entering the duplexer 11 from the input port, so as to block the low-frequency useful signal and pass the high-frequency interference signal; the load resistor 11b is used for absorbing the high-frequency interference signal passing through the high-pass filter F1; the first low-pass filter F2 is used to filter the signal entering the duplexer 11 from the input port, so as to block the high-frequency interference signal and pass the low-frequency useful signal; the first low noise amplifier 11a is used for first-stage amplifying the low frequency useful signal passing through the first low pass filter F2 and then feeding the amplified signal to the second stage circuit I.
The second-stage circuit I comprises a second low-pass filter I12 and a second low-noise amplifier I12a, and the output end of the second low-pass filter I12 is connected with the input end of the second low-noise amplifier I12 a; the second-stage circuit II comprises a second low-pass filter II13 and a second low-noise amplifier II13a, and the output end of the second low-pass filter II13 is connected with the input end of the second low-noise amplifier II13 a; the output end of the first low noise amplifier 11a is connected with the input end of the second low-pass filter I12, the output end of the second low noise amplifier I12a is connected with the input end of the second low-pass filter II13, and the output end of the second low noise amplifier II13a is the output port of the device.
The method for extracting the weak signal and inhibiting the strong interference signal by adopting the device of the embodiment comprises the following steps:
first, a signal including a low-frequency useful signal, a low-noise signal of 800MHz or more, and a 1.2GHz interfering signal and higher harmonics having a power strength of 10dBm is input from the input port 31.
Then, the high-pass filter F1 of the duplexer 11 filters the signal entering the duplexer 11 from the input port 31, and blocks the low-frequency useful signal and passes through the high-frequency interference signal, and the load resistor 11b absorbs the high-frequency interference signal passing through the high-pass filter F1; specifically, the high-pass filter F1 realizes a passband above 1.2GHz, and the suppression degree to 800MHz is-50 dB; the 1.25GHz interference signal passes through the high-pass filter F1 in the duplexer 11, and is absorbed by the load resistor 11b of 50 ohms.
The first low-pass filter F2 of the duplexer 11 filters the signal entering the duplexer 11 from the input port 31, blocks the high-frequency interference signal and passes through the low-frequency useful signal, the useful signal DC-800 MHz passes through the first low-pass filter F2 in the duplexer 11 and enters the first low-noise amplifier 11a, and the first low-noise amplifier 11a performs a first-stage amplification on the low-frequency useful signal passing through the first low-pass filter F2 and then transmits the signal to the second low-pass filter I12 of the second-stage circuit I. Specifically, the first low-pass filter F2 realizes a pass band below 800MHz, and the suppression degree to 1.25GHz is-40 dB; the frequency range of the first low noise amplifier 11a is DC-200 MHz, the typical value of the noise coefficient in the working frequency band is 1.8dB, and the gain is 23 dB.
Then, the second low-pass filter I12 performs filtering again on the signal subjected to the first-stage amplification, removes the high-frequency interference signal amplified by the first low-noise amplifier 11a, namely performs second suppression on the 1.25GHz interference signal, inputs the signal to the second low-noise amplifier I12a, and the second low-noise amplifier I12a performs second-stage amplification on the signal and then transmits the signal to the second low-pass filter II13 of the second-stage circuit II; specifically, the second low-pass filter I12 realizes a pass band below 800MHz, and the suppression degree of 1.25GHz is-40 dB; the frequency ranges of the second low noise amplifier I12a are both DC-200 MHz, the typical value of the noise coefficient in the working frequency band is 1.8dB, and the gain is 23 dB.
Then, the second low-pass filter II13 performs filtering again on the signal amplified in the second stage, further removes the high-frequency interference signal amplified by the second low-noise amplifier I12a, that is, performs third suppression on the 1.25GHz interference signal, inputs the signal to the second low-noise amplifier II13a, and outputs the signal from the output port 32 after the signal is amplified in the third stage by the second low-noise amplifier II13 a. Specifically, the second low-pass filter II13 realizes a pass band below 800MHz, and has a suppression degree of-40 dB to 1.25 GHz; the frequency ranges of the second low noise amplifier II13a are both DC-200 MHz, the typical value of the noise coefficient in the working frequency band is 1.8dB, and the gain is 23 dB.
Finally, a low-frequency useful signal is obtained from the output port 32, and a high-frequency interference signal is absorbed at the load resistor 11b and suppressed in the second low-pass filter I12 and the second low-pass filter II 13.
In this example, the interference signal and the useful signal are separated by the duplexer 11, and the interference signal entering each stage of low-pass filtering and amplifying circuit is greatly reduced, so that the requirement of the low-pass filter in the subsequent circuit on the suppression degree of the interference signal of 1.2GHz is greatly reduced, the order of the low-pass filter is effectively reduced, the design difficulty is reduced, and the size of the filtering circuit is reduced.
The embodiment realizes the extraction of the useful low-frequency weak signals of the DC-800 MHz frequency band, amplifies the useful signals from-67 dBm to about-7 dBm, wherein, the useful signals of the 10 KHz-800 MHz frequency band are extracted and amplified, and the useful signals can be amplified from-67 dBm to about 0 dBm; meanwhile, the deep suppression of the strong interference signal of 1.25GHz is realized, and the suppression degree is more than 140 dBc.
As shown in fig. 2, the simulation result of the output gain in the frequency range of DC-800 MHz is greater than 68dB, the suppression on the interference signal of 1.25GHz is greater than 96dBc (adding 68dB of gain, the actual suppression is greater than 160 dBc), the suppression on the higher harmonic wave of 2.5GHz is greater than 33dBc (adding 68dB of gain, the actual suppression is greater than 100 dBc), and the extraction of the weak signal and the deep suppression of the strong interference signal are realized.
As a preferred embodiment of this example, as shown in fig. 3 to 5, the apparatus further includes a cavity 3, the cavity 3 is divided into 3 chambers by 2 metal partitions 33: a first chamber 301, a second chamber 302, a third chamber 303; the first stage circuit is disposed in the first chamber 301, the second stage circuit I is disposed in the second chamber 302 adjacent to the first chamber 301, and the second stage circuit II is disposed in the third chamber 303 adjacent to the second chamber 302.
An input port 31 is arranged at one end of the cavity 3 and used as an input port of the device, the input port 31 is communicated to the first cavity 301, and the input end of the duplexer 11 is connected with the input port 31 through the microstrip line 4; the other end of the cavity 3 is provided with an output port 32 which is used as an output port of the device, the output port 32 is communicated to the third cavity 303, and the output end of the second low-noise amplifier II13a is connected with the output port 32 through the microstrip line 4; the output end of the first low-pass filter F2 is connected with the first low-noise amplifier 11a through the microstrip line 4; the output end of the high-pass filter F1 is connected with a load resistor 11b through a microstrip line 4; the output end of the first low-noise amplifier 11a passes through the corresponding metal partition 33 through the microstrip line 4 to extend out of the second cavity 302 and is connected with the input end of the second low-pass filter I12; the output end of the second low-pass filter I12 is connected with a second low-noise amplifier I12a through a microstrip line 4; the output end of the second low-noise amplifier I12a passes through the corresponding metal partition plate 33 through the microstrip line 4 to extend out of the third chamber 303 and is connected with the input end of the second low-pass filter II 13; the output end of the second low-pass filter II13 is connected to the second low-noise amplifier II13a through the microstrip line 4.
By arranging the circuits in an independent chamber respectively and realizing mutual isolation by utilizing the metal partition plate 33, signal interference is avoided, the electromagnetic compatibility is improved, and the influence on output signals is reduced to a lower level.
The devices/circuits are connected through the microstrip line 4, and are connected by using an opening at the metal partition plate 33, and the distance between the edge of the opening and the microstrip line 4 is as small as possible, so that no interference signal is leaked at the opening to the next stage of circuit.
As a further preferred embodiment of this example, a dielectric plate 34 is disposed in the cavity 3, the metal partition 33 is disposed on the front surface of the dielectric plate 34, a metal cover 35 is disposed on the top of the cavity 3, the metal cover 35, the front surface of the dielectric plate 34, and the metal partition 33 together form a first cavity 301, a second cavity 302, and a third cavity 303, and the first stage circuit, the second stage circuit I, and the second stage circuit II are disposed on the front surface of the dielectric plate 34. Clamping grooves are formed in two side walls of the cavity 3, the metal partition plate 33 is arranged in the clamping grooves, a groove is formed in the bottom surface of the metal cover 35, and the groove is matched with the top of the metal partition plate 33. The back of the dielectric plate 34 is provided with a power supply circuit 24, the power supply circuit 24 is connected with a power supply port 25, the power supply port 25 is arranged on the side wall of the cavity 3, the dielectric plate 34 is provided with a first power supply through hole 21 positioned in the first cavity 301, a second power supply through hole 22 positioned in the second cavity 302 and a third power supply through hole 23 positioned in the third cavity 303, the first-stage circuit is connected with the power supply circuit 24 through the first power supply through hole 21, the second-stage circuit I is connected with the power supply circuit 24 through the second power supply through hole 22, and the second-stage circuit II is connected with the power supply circuit 24 through the third power supply through hole 23.
Through the structural design, the first-stage circuit, the second-stage circuit and the power supply circuit are respectively positioned on the front side and the back side of the dielectric plate, power is supplied to the back side, filtering and amplification extraction are performed on the front side, each power supply through hole is ingeniously utilized for electrical connection, and mutual interference is reduced while the structural compactness and the integration are guaranteed.
The foregoing is only a preferred embodiment of the present invention and is not intended to be exhaustive or to limit the invention. It will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention.
Claims (10)
1. A device for extracting weak signals and suppressing strong interference signals is characterized by comprising a first-stage circuit and at least one second-stage circuit which are sequentially connected;
the first-stage circuit comprises a duplexer (11), a first low-noise amplifier (11 a) and a load resistor (11 b), the duplexer (11) comprises a first low-pass filter (F2) and a high-pass filter (F1), the input ends of the first low-pass filter (F2) and the high-pass filter (F1) are input ports of the device, the input end of the first low-noise amplifier (11 a) is connected with the output end of the first low-pass filter (F2), one end of the load resistor (11 b) is connected with the output end of the high-pass filter (F1), and the other end of the load resistor is grounded;
the second-stage circuit comprises a second low-pass filter and a second low-noise amplifier, and the output end of the second low-pass filter is connected with the input end of the second low-noise amplifier;
when one second-stage circuit is adopted, the output end of the first low-noise amplifier (11 a) is connected with the input end of the second low-pass filter, and the output end of the second low-noise amplifier is the output port of the device;
when the second-stage circuit is multiple, the output end of the first low-noise amplifier (11 a) is connected with the input end of the second low-pass filter of the first second-stage circuit, the output end of the second low-noise amplifier of the previous second-stage circuit is connected with the input end of the second low-pass filter of the next second-stage circuit, and the output end of the second low-noise amplifier of the last second-stage circuit is the output port of the device.
2. The apparatus of claim 1, wherein the apparatus for extracting weak signals and suppressing strong interference signals comprises: the high-pass filter (F1) is used for filtering the signal entering the duplexer (11) from the input port so as to prevent the low-frequency useful signal and pass the high-frequency interference signal;
the load resistor (11 b) is used for absorbing the high-frequency interference signal passing through the high-pass filter (F1);
a first low-pass filter (F2) for filtering the signal entering the diplexer (11) from the input port to block high-frequency interfering signals and pass low-frequency wanted signals;
the first low noise amplifier (11 a) is used for carrying out primary amplification on the low-frequency useful signal passing through the first low-pass filter (F2) and then transmitting the low-frequency useful signal to the second-stage circuit;
the second low-pass filter is used for further filtering the amplified signal input into the second-stage circuit;
the second low noise amplifier is used for carrying out secondary amplification on the signal filtered by the second low pass filter.
3. The apparatus of claim 1, wherein the apparatus for extracting weak signals and suppressing strong interference signals comprises: two second-stage circuits are provided, including a second-stage circuit I and a second-stage circuit II;
the second-stage circuit I comprises a second low-pass filter I (12) and a second low-noise amplifier I (12 a), and the output end of the second low-pass filter I (12) is connected with the input end of the second low-noise amplifier I (12 a);
the second-stage circuit II comprises a second low-pass filter II (13) and a second low-noise amplifier II (13 a), and the output end of the second low-pass filter II (13) is connected with the input end of the second low-noise amplifier II (13 a);
the output end of the first low-noise amplifier (11 a) is connected with the input end of the second low-pass filter I (12), the output end of the second low-noise amplifier I (12 a) is connected with the input end of the second low-pass filter II (13), and the output end of the second low-noise amplifier II (13 a) is the output port of the device.
4. A device for extracting weak signals and suppressing strong interference signals according to claim 3, further comprising a chamber (3), wherein the chamber (3) is divided into 3 chambers by 2 metal partitions (33): a first chamber (301), a second chamber (302), a third chamber (303); the first stage circuit is arranged in the first cavity (301), the second stage circuit I is arranged in the second cavity (302) adjacent to the first cavity (301), and the second stage circuit II is arranged in the third cavity (303) adjacent to the second cavity (302).
5. An apparatus for extracting weak signals and suppressing strong interference signals according to claim 4, wherein: one end of the cavity (3) is provided with an input port (31) which is used as an input port of the device, the input port (31) is communicated to the first cavity (301), and the input end of the duplexer (11) is connected with the input port (31) through a microstrip line (4);
the other end of the cavity (3) is provided with an output port (32) which is used as an output port of the device, the output port (32) is communicated to the third cavity (303), and the output end of the second low-noise amplifier II (13 a) is connected with the output port (32) through a microstrip line (4);
the output end of the first low-pass filter (F2) is connected with a first low-noise amplifier (11 a) through a microstrip line (4);
the output end of the high-pass filter (F1) is connected with a load resistor (11 b) through a microstrip line (4);
the output end of the first low-noise amplifier (11 a) penetrates through the corresponding metal partition plate (33) through a microstrip line (4) to extend out of the second cavity (302) and is connected with the input end of the second low-pass filter I (12);
the output end of the second low-pass filter I (12) is connected with a second low-noise amplifier I (12 a) through a microstrip line (4);
the output end of the second low-noise amplifier I (12 a) penetrates through the corresponding metal partition plate (33) through a microstrip line (4) to extend out of the third chamber (303) and is connected with the input end of a second low-pass filter II (13);
the output end of the second low-pass filter II (13) is connected with a second low-noise amplifier II (13 a) through a microstrip line (4).
6. An apparatus for extracting weak signals and suppressing strong interference signals according to claim 4, wherein: be equipped with dielectric-slab (34) in cavity (3), metal baffle (33) are located dielectric-slab (34) openly, and cavity (3) top is equipped with metal cover (35), and metal cover (35), dielectric-slab (34) are positive, metal baffle (33) form first cavity (301), second cavity (302), third cavity (303) jointly, and first level circuit, second level circuit I, second level circuit II all locate dielectric-slab (34) openly.
7. An apparatus for extracting weak signals and suppressing strong interference signals according to claim 6, wherein: the back of the dielectric plate (34) is provided with a power supply circuit (24), the power supply circuit (24) is connected with a power supply port (25), the power supply port (25) is arranged on the side wall of the cavity (3), the dielectric plate (34) is provided with a first power supply through hole (21) located in the first cavity (301), a second power supply through hole (22) located in the second cavity (302), a third power supply through hole (23) located in the third cavity (303), the first-stage circuit is connected with the power supply circuit (24) through the first power supply through hole (21), the second-stage circuit I is connected with the power supply circuit (24) through the second power supply through hole (22), and the second-stage circuit II is connected with the power supply circuit (24) through the third power supply through hole (23).
8. An apparatus for extracting weak signals and suppressing strong interference signals according to claim 6, wherein: clamping grooves are formed in two side walls of the cavity (3), the metal partition plate (33) is arranged in the clamping grooves, grooves are formed in the bottom surface of the metal cover (35), and the grooves are matched with the tops of the metal partition plate (33).
9. A method for extracting weak signals and suppressing strong interference signals, which is performed by the device for extracting weak signals and suppressing strong interference signals according to any one of claims 5-8, comprising the steps of:
a high-pass filter (F1) of the duplexer (11) filters a signal entering the duplexer (11) from the input port (31) to block a low-frequency useful signal and pass a high-frequency interference signal, and a load resistor (11 b) absorbs the high-frequency interference signal passing through the high-pass filter (F1);
a first low-pass filter (F2) of the duplexer (11) filters a signal entering the duplexer (11) from the input port (31) and blocks a high-frequency interference signal and passes a low-frequency useful signal, and a first low-noise amplifier (11 a) performs primary amplification on the low-frequency useful signal passing through the first low-pass filter (F2) and then transmits the amplified signal to a second low-pass filter I (12) of a second-stage circuit I;
the second low-pass filter I (12) filters the signal amplified in the first stage again, after removing the high-frequency interference signal amplified by the first low-noise amplifier (11 a), the signal is input into the second low-noise amplifier I (12 a), the second low-noise amplifier I (12 a) amplifies the signal in the second stage and then transmits the signal to the second low-pass filter II (13) of the second-stage circuit II;
the second low-pass filter II (13) filters the signals amplified in the second stage again, further removes high-frequency interference signals amplified by the second low-noise amplifier I (12 a), inputs the signals to the second low-noise amplifier II (13 a), and outputs the signals from an output port (32) after the second low-noise amplifier II (13 a) amplifies the signals in the third stage;
finally, a low-frequency useful signal is obtained from the output port (32), and a high-frequency interference signal is absorbed at the load resistor (11 b) and suppressed in the second low-pass filter I (12) and the second low-pass filter II (13).
10. Method for extracting weak signals and suppressing strong interfering signals according to claim 9, characterized in that the signals entering the duplexer (11) from the input port (31) include low frequency useful signals, low noise signals above 800MHz and 1.2GHz interfering signals with a power strength of 10dBm and higher harmonics; the high-pass filter (F1) is used for realizing a passband above 1.2GHz, and the rejection degree of 800MHz is-50 dB; the first low-pass filter (F2), the second low-pass filter I (12) and the second low-pass filter II (13) are all used for realizing a pass band below 800MHz, and the degree of inhibition to 1.25GHz is-40 dB; the frequency ranges of the first low noise amplifier (11 a), the second low noise amplifier I (12 a) and the second low noise amplifier II (13 a) are all DC-200 MHz, the typical value of the noise coefficient in the working frequency band is 1.8dB, and the gain is 23 dB.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110641276.8A CN113258883B (en) | 2021-06-09 | 2021-06-09 | Device and method for extracting weak signal and suppressing strong interference signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110641276.8A CN113258883B (en) | 2021-06-09 | 2021-06-09 | Device and method for extracting weak signal and suppressing strong interference signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113258883A CN113258883A (en) | 2021-08-13 |
| CN113258883B true CN113258883B (en) | 2021-11-02 |
Family
ID=77187338
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110641276.8A Active CN113258883B (en) | 2021-06-09 | 2021-06-09 | Device and method for extracting weak signal and suppressing strong interference signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113258883B (en) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007295327A (en) * | 2006-04-26 | 2007-11-08 | Hitachi Metals Ltd | High frequency circuit, high frequency component, and communication apparatus |
| JP4837591B2 (en) * | 2007-02-13 | 2011-12-14 | オンセミコンダクター・トレーディング・リミテッド | FM receiver |
| CN201360254Y (en) * | 2009-02-23 | 2009-12-09 | 青岛海信移动通信技术股份有限公司 | Interference-suppressing circuit and mobile communication terminal with the circuit |
| CN201976071U (en) * | 2011-04-15 | 2011-09-14 | 广州海格通信集团股份有限公司 | Front-end amplifier of wireless communication receiver |
| CN202737816U (en) * | 2012-08-01 | 2013-02-13 | 天水七四九电子有限公司 | Low noise signal detection conversion amplification circuit |
| CN103401509A (en) * | 2013-07-03 | 2013-11-20 | 吴江市同心电子科技有限公司 | Multichannel low noise amplifier |
| CN210958286U (en) * | 2020-02-10 | 2020-07-07 | 四川华讯新科科技有限公司 | Radio frequency front end amplifying circuit of radio frequency identification label chip |
| CN213244021U (en) * | 2020-11-17 | 2021-05-18 | 深圳市航达微电子技术有限公司 | C-band anti-5G interference LNA |
-
2021
- 2021-06-09 CN CN202110641276.8A patent/CN113258883B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113258883A (en) | 2021-08-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6500913B2 (en) | High frequency circuit component and communication device | |
| CN206259922U (en) | RF front-end module and mobile terminal | |
| KR102438877B1 (en) | High-frequency modules and communication devices | |
| US20020145490A1 (en) | Filter structure including circuit board | |
| CN110311196B (en) | 5G dual-passband filter based on dielectric integrated suspension line | |
| CN113411062B (en) | Matching circuit, radio frequency front end power amplifying circuit and mobile communication equipment | |
| Xie et al. | A K-band high interference-rejection GaAs low-noise amplifier using multizero control method for satellite communication | |
| CN210297678U (en) | UHF frequency channel airborne transmitting radio frequency circuit | |
| CN113258883B (en) | Device and method for extracting weak signal and suppressing strong interference signal | |
| CN117639721A (en) | Ultra-narrow bandwidth VHF frequency band receiving and transmitting filter bank | |
| CN103001587A (en) | X-frequency-range extra-low inter-modulation frequency converter device of measurement and control system | |
| KR950003104B1 (en) | Microwave multistage amplifier | |
| CN113328223A (en) | Third-order band-pass filter | |
| CN215581117U (en) | Antenna diplexer circuit and power amplifier transmitting module | |
| CN113824464A (en) | Antenna diplexer circuit, power amplifier transmitting module and mobile communication equipment | |
| CN213484821U (en) | Frequency conversion assembly for electronic warfare and surveillance equipment | |
| CN210629432U (en) | S-band solid-state power amplifier assembly | |
| CN115250095A (en) | Power amplifying module | |
| Konpang et al. | Four-port microstrip diplexer for RF interference rejection | |
| KR100729969B1 (en) | Repeater having dielectric band stop resonators | |
| CN115276568B (en) | Miniaturized filtering low-noise amplifier and receiver | |
| CN216248804U (en) | Quick response high isolation program control matrix switch | |
| CN220629330U (en) | Double-receiving and transmitting integrated co-feeder | |
| CN219780137U (en) | Multichannel short wave receiving and transmitting circuit | |
| KR101027032B1 (en) | Output units for mobile telecommunication equipments |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |