WO2018010242A1

WO2018010242A1 - Monitoring system based on terahertz communication

Info

Publication number: WO2018010242A1
Application number: PCT/CN2016/094501
Authority: WO
Inventors: 陈文健; 杨彬; 丁庆
Original assignee: 深圳市太赫兹科技创新研究院; 华讯方舟科技有限公司
Priority date: 2016-07-12
Filing date: 2016-08-11
Publication date: 2018-01-18
Also published as: CN106027994B; CN106027994A

Abstract

A monitoring system based on terahertz communication, the monitoring system comprising cameras (10), access switches (20), aggregation switches (30) and a core switch (40); each of a plurality of cameras (10) is correspondingly connected to one access switch (20) via a CAT5 network cable, each of a plurality of access switches (20) is correspondingly connected to one aggregation switch (30) via a CAT5 network cable, and a plurality of aggregation switches (30) communicate wirelessly with one core switch (40) through terahertz waves. In the present application, data transmission between the core switch (40) and the plurality of aggregation switches (30) of the monitoring system is achieved by using terahertz waves, which makes it possible to effectively improve communication efficiency and to improve communication quality such that a high-level switch port of the monitoring system can be connected to more video management devices, thereby allowing for more monitoring services and effectively reducing the amount of cabling.

Description

Specification Name of Invention: A Monitoring System Based on Terahertz Communication

[0001] The present invention belongs to the field of monitoring, and in particular, to a monitoring system based on terahertz communication.

Background technique

[0002] The security monitoring system is an electronic system or network that uses video technology to detect and monitor the fortified area to display and record the image of the fortified area. In a large-scale security monitoring system, hundreds of thousands of network cameras are usually used, and the cameras are hierarchically managed according to the user's monitoring and management requirements to realize monitoring of commercial buildings, large communities, factories and other areas.

[0003] However, the existing security monitoring system usually uses five types of network cables to transmit the monitoring data captured by the camera, resulting in a large number of cameras or a high-resolution camera for monitoring, due to excessive data volume. Transmission efficiency is reduced and wiring is complicated.

technical problem

[0004] An object of the present invention is to provide a monitoring system based on terahertz communication, which aims to solve the problem that the existing security monitoring system generally uses five types of network cables to transmit monitoring data captured by the camera, resulting in a large number of cameras or high selection. When the resolution camera is monitored, the data transmission efficiency is lowered and the wiring is complicated due to the excessive amount of data. Problem solution

Technical solution

[0005] The present invention is implemented in this manner, a monitoring system based on terahertz communication, the monitoring system including a camera, an access switch, an aggregation switch, and a core switch;

[0006] A plurality of the cameras are connected to one of the access switches through a network of five types, and the plurality of access switches are connected to one of the aggregation switches through five types of network cables, and the plurality of aggregation switches pass the terahertz wave. Wirelessly communicating with one of the core switches;

[0007] the access switch acquires monitoring data captured by a camera connected thereto, and performs encoding and modulation processing to output a first intermediate frequency signal to an aggregation switch connected thereto; the aggregation switch inputs an output of an access switch connected thereto First IF signal, and mixing processing into a first terahertz RF signal And transmitting to the core switch with which the wireless switch communicates; the core switch receives the first terahertz radio frequency signal transmitted by the aggregation switch with which it wirelessly communicates, and performs mixing, demodulation, and decoding processing to obtain the monitoring data.

[0008] Preferably, the access switch includes a code modulation module;

[0009] the code modulation module acquires monitoring data captured by a camera connected to the access switch, and performs encoding and modulation processing to output a first intermediate frequency signal to an aggregation switch connected to the access switch.

[0010] Preferably, the code modulation module includes a source coding unit and a modulation unit connected to the source coding unit;

[0011] the source coding unit performs encoding processing on the monitoring data captured by the camera connected to the access switch, and outputs the monitoring data to the modulation unit, and the modulation unit performs modulation processing on the monitoring data after the encoding process. The first intermediate frequency signal is described.

[0012] Preferably, the aggregation switch comprises a terahertz transmitter;

[0013] wherein the terahertz transmitter includes a first local oscillator signal filter, a first harmonic mixer, and a first radio frequency signal filter that are sequentially connected;

[0014] the first local oscillator signal filter is connected to the first local oscillator signal, and is filtered and output to the first harmonic mixer; the first harmonic mixer will filter The first first local oscillator signal and the first intermediate frequency signal input by the aggregation switch are mixed and processed into a first terahertz radio frequency signal, and output to the first radio frequency signal filter; the first radio frequency signal filter The first terahertz RF signal output by the first harmonic mixer is filtered and transmitted to a core switch that wirelessly communicates with the aggregation switch.

[0015] Preferably, the first local oscillator signal filter and the first radio frequency signal filter are both band pass filters

[0016] Preferably, the terahertz transmitter further includes a first frequency multiplier, a first amplifier, a first local oscillator signal isolator, and a first low noise amplifier and a first radio frequency signal isolator connected in sequence. The output end of the first local oscillator signal isolator is connected to the input end of the first local oscillator signal filter, and the input end of the first low noise amplifier is connected to the output end of the first radio frequency signal filter;

[0017] the first local oscillation signal sequentially passes through the first frequency multiplier, the first amplifier, and the first local vibration signal The frequency doubling, amplification and isolation processing of the isolator is output to the first local oscillator signal filter, and the first terahertz radio frequency signal filtered by the first radio frequency signal filter is sequentially subjected to the first low noise The amplifier and the first RF signal isolator are amplified and isolated and transmitted to a core switch in wireless communication with the aggregation switch.

[0018] Preferably, the core switch includes a terahertz receiver and a demodulation decoding module connected to the terahertz receiver;

[0019] wherein the terahertz receiver comprises a second local oscillator signal filter and a second harmonic mixer connected to the second local oscillator signal filter;

[0020] the second local oscillator signal filter is connected to the second local oscillator signal, and is filtered and output to the second harmonic mixer; the second harmonic mixer will filter The second second local oscillator signal is mixed with the first terahertz radio frequency signal transmitted by the aggregation switch wirelessly communicated with the core switch into a second intermediate frequency signal, and the demodulation and decoding module performs the second intermediate frequency signal. Demodulation and decoding processes result in monitoring data.

[0021] Preferably, the demodulation and decoding module includes a second demodulation unit and a second decoding unit connected to the second demodulation unit;

[0022] The second demodulation unit demodulates the second intermediate frequency signal output by the terahertz receiver and outputs the result to the second decoding unit, where the second decoding unit performs demodulation processing The second intermediate frequency signal is subjected to decoding processing to obtain the monitoring data.

[0023] Preferably, the second local oscillator signal filter is a band pass filter.

[0024] Preferably, the terahertz receiver further includes a second frequency multiplier, a second amplifier, a second local oscillator signal isolator, and a second low noise amplifier and a second radio frequency signal isolator connected in sequence. The output end of the second local oscillator signal isolator is connected to the input end of the second local oscillator signal filter, and the input end of the second low noise amplifier is connected to the second harmonic mixer;

[0025] the second local oscillation signal is sequentially output to the second by frequency multiplication, amplification, and isolation processing of the second frequency multiplier, the second amplifier, and the second local oscillator signal isolator a local oscillator signal filter, the first terahertz radio frequency signal transmitted by the aggregation switch wirelessly communicating with the core switch is sequentially amplified and isolated by the second low noise amplifier and the second radio frequency signal isolator, and output To the second harmonic mixer. Advantageous effects of the invention

Beneficial effect

[0026] Compared with the prior art, the present invention has the beneficial effects of:

[0027] By using terahertz waves to implement data transmission between the core switch of the monitoring system and multiple aggregation switches, communication efficiency can be effectively improved, communication quality can be improved, and higher-level switch ports of the monitoring system can be connected to more video management. Equipment, expands more monitoring services and reduces the amount of wiring. Brief description of the drawing

DRAWINGS

1 is a structural block diagram of a monitoring system based on terahertz communication according to Embodiment 1 of the present invention;

2 is a schematic diagram of an application of a monitoring system based on terahertz communication according to Embodiment 1 of the present invention; [0030] FIG. 3 is a structural block diagram of a monitoring system based on terahertz communication provided by Embodiment 2 of the present invention;

4 is a structural block diagram of a terahertz transmitter according to Embodiment 2 of the present invention;

5 is a structural block diagram of a terahertz receiver according to Embodiment 2 of the present invention;

6 is a structural block diagram of a terahertz transmitter according to Embodiment 3 of the present invention;

7 is a structural block diagram of a terahertz receiver according to Embodiment 3 of the present invention;

8 is a structural block diagram of an access switch according to Embodiment 4 of the present invention;

9 is a structural block diagram of a core switch according to Embodiment 4 of the present invention.

Embodiments of the invention

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0038] Embodiment 1:

As shown in FIG. 1, the terahertz communication-based monitoring system provided by the present embodiment includes a camera 10, an access switch 20, an aggregation switch 30, and a core switch 40.

[0040] A plurality of the cameras 10 are connected to one access switch 20 through a five types of network cables, and multiple access switches are provided.

20 is connected to one aggregation switch 30 through five types of network cables, and the plurality of aggregation switches 30 pass the terahertz wave. Wireless communication with a core switch 40.

[0041] In a specific application, the number of the camera 10, the access switch 20, the aggregation switch 30, and the core switch 40 may be specifically set according to the size of the actual monitoring area and other monitoring requirements. In some cases, the camera 10, The number of the ingress switch 20 and the aggregation switch 30 may be one or two and is not limited to a plurality. The number of the core switches 40 may also be two or more.

[0042] The access switch 20 acquires the monitoring data captured by the camera 10 connected thereto, and performs encoding and modulation processing to output the first intermediate frequency signal to the aggregation switch 30 connected thereto; the aggregation switch 30 inputs the output of the access switch 20 connected thereto. The first intermediate frequency signal is subjected to mixing processing to transmit the first terahertz radio frequency signal to the core switch 40 wirelessly communicating therewith; the core switch 40 receives the first terahertz radio frequency signal transmitted by the aggregation switch 20 in wireless communication with the core switch 40, and performs The monitoring, demodulation and decoding processes result in the monitoring data.

[0043] In a specific application, the core switch 40 acquires a control signal input by the user, and transmits it to the aggregation switch 30 that communicates with the wireless signal through the wireless signal transmitting device; the aggregation switch 30 receives the core switch 40 with which the wireless communication communicates with the control signal, and outputs The access switch 20 to which it is connected; the access switch 20 inputs a control signal output from the aggregation switch 30 connected thereto and outputs it to the camera 10 connected thereto.

[0044] The device such as the core switch and the aggregation switch that communicate by default in the wireless communication mode includes an antenna for receiving and transmitting a wireless signal, which is not specifically described in this embodiment. In this embodiment, a 0. 14 THz ring-focus polarized antenna is used, the gain is 51 dB, the antenna paraboloid diameter is 320 mm, and the interface is a WR6 rectangular waveguide.

[0045] In this embodiment, the terahertz wave is used to implement data transmission between the core switch of the monitoring system and multiple aggregation switches, which can effectively improve communication efficiency, improve communication quality, and enable the switch port of the monitoring system to connect more. Cameras, expand more monitoring services and reduce the amount of wiring.

[0046] As shown in FIG. 2, it is a schematic diagram of the application of the terahertz communication-based monitoring system provided in this embodiment in a specific application.

[0047] In this embodiment, the monitoring system is set to be applied to a monitoring area including a plurality of buildings, and each building includes a plurality of floors. In the present embodiment, only three buildings are shown for convenience of description, and specific The settings of the cameras, access switches, and aggregation switches in the three floors of one of the buildings are shown.

[0048] As shown in FIG. 2, a plurality of cameras are disposed in one layer, two layers, and N layers of the first building (this embodiment) For the convenience of illustration, only six cameras are shown at a time. The cameras on each floor are connected to the access switches installed on the floor through five types of network cables. The access switches on the first, second and N floors are The five types of network cables are connected to the aggregation switches installed on the first floor of the first building. The settings of the cameras, access switches and aggregation switches in the second and Nth buildings are similar to those of the first one;

[0049] The aggregation switches of multiple buildings transmit the monitoring data captured by all the cameras of the entire building to the core switch located in the monitoring center through terahertz communication, so that the staff of the monitoring center can pass multiple pairs of core switches. Building monitoring;

[0050] In a specific application, when the staff of the monitoring center wants to control the cameras in multiple buildings, the core switch can transmit wireless control signals to the aggregation switches in multiple buildings, and then the aggregation switch passes. The five types of network cables are transmitted to the access switches of each floor, and finally transmitted to the corresponding cameras through the access switches to realize the control of the cameras.

[0051] Embodiment 2:

As shown in FIG. 3, in this embodiment, the access switch 20 includes a code modulation module 21, and an aggregation switch 3

0 includes a terahertz transmitter 31, and the core switch 40 includes a terahertz receiver 41 and a demodulation decoding module 42 coupled to the terahertz receiver 41.

As shown in FIG. 4, in the present embodiment, the terahertz transmitter 31 includes a first local oscillation signal filter 311, a first harmonic mixer 312, and a first radio frequency signal filter 313 which are sequentially connected. .

As shown in FIG. 5, in the present embodiment, the terahertz receiver 41 includes a second local oscillator signal filter 411 and a second harmonic mixer 412 connected to the second local oscillator signal filter 411. .

[0055] In an embodiment, the first local oscillator signal filter, the first radio frequency signal filter, and the second local oscillator signal filter are band pass filters.

[0056] In this embodiment, the principle that the aggregation switch 30 transmits the monitoring data captured by the camera 10 to the core switch 40 is as follows:

[0057] The code modulation module 21 acquires the monitoring data captured by the camera 10 connected to the access switch 21, and performs encoding and modulation processing to output the first intermediate frequency signal to the aggregation switch 30 connected to the access switch 20;

[0058] the first local oscillator signal filter is connected to the first local oscillator signal, and is filtered and output to the first harmonic mixer; the first harmonic mixer will filter The first first local oscillator signal and the first intermediate frequency signal input by the aggregation switch 30 are mixed and processed into a first terahertz RF signal, and output to The first radio frequency signal filter: the first radio frequency signal filter filters the first terahertz radio frequency signal output by the first harmonic mixer, and transmits the first terahertz radio frequency signal to a core switch that wirelessly communicates with the aggregation switch 30. 40;

[0059] the second local oscillator signal filter is connected to the second local oscillator signal, and is filtered and output to the second harmonic mixer; the second harmonic mixer will filter The second second local oscillator signal is mixed with the first terahertz radio frequency signal transmitted by the aggregation switch 30 wirelessly communicated with the core switch 40 into a second intermediate frequency signal, and the demodulation and decoding module performs the second intermediate frequency signal. Demodulation and decoding processes result in monitoring data.

[0060] The first and second in this embodiment are only for distinguishing the components with the same principle and structure in different devices.

, does not have a substantive meaning.

[0061] In a specific application, the aggregation switch may also include a terahertz receiver for receiving terahertz signals transmitted by other terahertz transmitters, and the working principle is the same as that of the above terahertz receiver; the core switch may also include terahertz Transmitter, used to transmit terahertz signals to other terahertz receivers, operating in the same way as the terahertz transmitter described above.

[0062] The subharmonic mixer in this embodiment is a Schottky diode based 0.14THZ second harmonic mixer with an upconversion loss of 7 dB, a down conversion loss of 13 dB, and a bandwidth of 10 GHz; The local oscillator signal input by the transmitter and the terahertz receiver has a frequency of 32.4 GHz and a power of -5 dBm; the input intermediate frequency signal has a frequency of 6 GHz and the power is -5 dBm; the center frequency of the output intermediate frequency signal is 135.6 GHz and 12 respectively. Upper and lower sidebands of 3.6 GHz (with a bandwidth of 3.6 GHz).

Embodiment 3:

As shown in FIG. 6, in the embodiment, the terahertz transmitter 31 further includes a first frequency multiplier 314, a first amplifier 315, a first local oscillator signal isolator 316, and a sequentially connected first. a low noise amplifier 317 and a first RF signal isolator 318, an output of the first local oscillator signal isolator 316 is connected to an input end of the first local oscillator signal filter 311, and an input of the first low noise amplifier 317 The output of the first RF signal filter 313 is terminated.

[0065] the first local oscillation signal is sequentially output to the first frequency multiplier 314, the first amplifier 315, and the first local oscillator signal isolator 316 by frequency multiplication, amplification, and isolation. a first local oscillator signal filter 311, and the first terahertz radio frequency signal filtered by the first radio frequency signal filter 313 is sequentially subjected to The amplification and isolation processing of the first low noise amplifier 317 and the first radio frequency signal isolator 318 are transmitted to the core switch 40 in wireless communication with the aggregation switch 30.

As shown in FIG. 7, in the embodiment, the terahertz receiver 41 further includes a second frequency multiplier 413, a second amplifier 414, a second local oscillator signal isolator 415, and a serial connection. The second low noise amplifier 416 and the second radio frequency signal isolator 417, the output end of the second local oscillator signal isolator 415 is connected to the input end of the second local oscillator signal filter 411, the second low noise An input of amplifier 416 is coupled to an input of said second harmonic mixer 412.

[0067] the second local oscillation signal is sequentially output to the second frequency multiplier 413, the second amplifier 414, and the second local oscillator signal isolator 415 by frequency multiplication, amplification, and isolation. The second local oscillator signal filter 411, the first terahertz radio frequency signal transmitted by the aggregation switch 30 in wireless communication with the core switch 40 is sequentially passed through the second low noise amplifier 417 and the second radio frequency signal isolator 416. After the amplification and isolation processing, the second harmonic mixer 412 is output.

[0068] In this embodiment, by multiplying, amplifying, and isolating the signal, the signal quality can be effectively improved and the loss can be reduced.

[0069] Delete:

[0070] As shown in FIG. 8, in the monitoring system based on terahertz communication provided in this embodiment, the code modulation module 2

1 includes a source coding unit 211 and a modulation unit 212 connected to the source coding unit 211.

[0071] As shown in FIG. 9, in the monitoring system based on terahertz communication provided in this embodiment, the demodulation and decoding module 4

2 includes a demodulation unit 421 and a decoding unit 422 connected to the demodulation unit 421.

[0072] The source encoding unit 211 performs encoding processing on the monitoring data captured by the camera 10 connected to the access switch 20, and outputs the monitoring data to the modulation unit 212, and the modulation unit 212 modulates the monitoring data after the encoding process. Processing results in the first intermediate frequency signal.

[0073] The demodulation unit 421 performs demodulation processing on the second intermediate frequency signal output by the terahertz receiver 41, and outputs the result to the decoding unit 422, where the decoding unit 422 performs the second intermediate frequency signal after the demodulation processing. The decoding process obtains the monitoring data.

[0074] In a specific application, the source encoding unit 211 performs RS on the monitoring data captured by the camera 10 (204, 18).

8) Source coding, single frame coding length is 2Mbit modulation unit 212 modulates the encoded monitoring data to 16

QAM baseband signal; demodulation unit 421 demodulates 16QAM baseband signal, decoding unit 422 The adjusted signal is RS (204, 188) coded and decoded to obtain monitoring data.

In this embodiment, by performing RS (204, 188) encoding and decoding on the signal and 16QAM switching modulation and demodulation, the bit error rate of the system can be effectively reduced, and the communication quality is improved.

The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, and improvements made within the spirit and scope of the present invention should be included in the present invention. Within the scope of protection of the invention.

Claims

Claim

[Claim 1] A monitoring system based on terahertz communication, wherein the monitoring system includes a camera, an access switch, an aggregation switch, and a core switch; and the plurality of cameras are connected to each other through five types of network cables. Accessing the switch, the plurality of access switches are connected to one of the aggregation switches through a network of five types, and the plurality of aggregation switches are wirelessly communicated with one of the core switches by using a terahertz wave; The camera captures the monitoring data, and performs encoding and modulation processing to output the first intermediate frequency signal to the aggregation switch connected thereto; the aggregation switch inputs the first intermediate frequency signal outputted by the access switch connected thereto, and performs mixing processing as Transmitting, transmitting, demodulating, and decoding the first terahertz radio frequency signal to a core switch with which the wireless switch communicates; the core switch receives the first terahertz radio frequency signal transmitted by the aggregation switch with which the wireless communication is performed, and obtains the monitoring data by performing mixing, demodulation, and decoding processing. .

[Claim 2] The terahertz communication-based monitoring system according to claim 1, wherein the access switch comprises a coded modulation module;

The code modulation module acquires monitoring data captured by a camera connected to the access switch, and performs encoding and modulation processing to output a first intermediate frequency signal to an aggregation switch connected to the access switch.

[Claim 3] The terahertz communication-based monitoring system according to claim 2, wherein the code modulation module includes a source coding unit and a modulation unit connected to the source coding unit;

The source encoding unit performs encoding processing on the monitoring data captured by the camera connected to the access switch, and outputs the monitoring data to the modulation unit, where the modulation unit performs modulation processing on the monitoring data after the encoding process to obtain the first IF signal.

[Claim 4] The terahertz communication-based monitoring system according to claim 1, wherein the aggregation switch comprises a terahertz transmitter;

The terahertz transmitter includes a first local oscillator signal filter, a first harmonic mixer, and a first radio frequency signal filter that are sequentially connected;

The first local oscillator signal filter is connected to the first local oscillator signal, and is filtered and processed for output. Giving the first harmonic mixer; the first harmonic mixer mixing the filtered first local oscillator signal and the first intermediate frequency signal input by the aggregation switch into a first a Hertz RF signal is output to the first RF signal filter; the first RF signal filter filters the first terahertz RF signal output by the first harmonic mixer and transmits the signal to the first Hz signal The core switch of the aggregation switch wireless communication.

[Claim 5] The terahertz communication-based monitoring system according to claim 4, wherein the first local oscillation signal filter and the first radio frequency signal filter are both band pass filters.

[Claim 6] The terahertz communication-based monitoring system according to claim 4, wherein the terahertz transmitter further includes a first frequency multiplier, a first amplifier, and a first local oscillator signal that are sequentially connected An isolator and a first low noise amplifier and a first radio frequency signal isolator connected in sequence, wherein an output end of the first local oscillator signal isolator is connected to an input end of the first local oscillator signal filter, the first low An input end of the noise amplifier is connected to the output of the first RF signal filter, and the first local oscillator signal is sequentially passed through the first frequency multiplier, the first amplifier, and the first local oscillator signal isolator. The frequency doubling, amplification and isolation processing is output to the first local oscillator signal filter, and the first terahertz radio frequency signal filtered by the first radio frequency signal filter is sequentially passed through the first low noise amplifier and the The amplification and isolation processing of the first RF signal isolator is transmitted to a core switch that wirelessly communicates with the aggregation switch.

[Claim 7] The terahertz communication-based monitoring system according to claim 1, wherein the core switch includes a terahertz receiver and a demodulation decoding module connected to the terahertz receiver;

The terahertz receiver includes a second local oscillator signal filter and a second harmonic mixer coupled to the second local oscillator signal filter;

The second local oscillator signal filter is connected to the second local oscillator signal, and is filtered and output to the second harmonic mixer; the second harmonic mixer will filter the first The second local oscillator signal and the first terahertz radio frequency signal transmitted by the aggregation switch wirelessly communicating with the core switch are mixed and processed into a second intermediate frequency signal, and the demodulation and decoding module demodulates the second intermediate frequency signal and The decoding process obtains monitoring data.

[Claim 8] The terahertz communication-based monitoring system according to claim 7, wherein the demodulation decoding module includes a second demodulation unit and a second decoding connected to the second demodulation unit Unit

The second demodulation unit demodulates the second intermediate frequency signal output by the terahertz receiver, and outputs the second intermediate frequency signal to the second decoding unit, where the second decoding unit performs the second intermediate frequency signal after the demodulation processing. The decoding process is performed to obtain the monitoring data.

[Claim 9] The terahertz communication-based monitoring system according to claim 7, wherein the second local oscillation signal filter is a band pass filter.

[Claim 10] The terahertz communication-based monitoring system according to claim 7, wherein the terahertz receiver further includes a second frequency multiplier, a second amplifier, and a second local oscillator signal that are sequentially connected An isolator and a second low noise amplifier and a second radio frequency signal isolator connected in sequence, wherein an output end of the second local oscillator signal isolator is connected to an input end of the second local oscillator signal filter, and the second low An input end of the noise amplifier is connected to the second harmonic mixer; the second local oscillation signal is sequentially passed through the second frequency multiplier, the second amplifier, and the second local oscillator signal isolator The frequency doubling, amplification and isolation processing is output to the second local oscillator signal filter, and the first terahertz radio frequency signal transmitted by the aggregation switch wirelessly communicating with the core switch is sequentially passed through the second low noise amplifier and the After amplification and isolation processing of the second RF signal isolator, output to the second harmonic mixer.