CN201860298U

CN201860298U - Linear channel amplifier

Info

Publication number: CN201860298U
Application number: CN2010205866188U
Authority: CN
Inventors: 周斌; 黄微波; 龚科; 张婷; 李红然
Original assignee: Xian Institute of Space Radio Technology
Current assignee: Xian Institute of Space Radio Technology
Priority date: 2010-10-27
Filing date: 2010-10-27
Publication date: 2011-06-08
Anticipated expiration: 2020-10-27

Abstract

A linear channel amplifier comprises an input end isolator, an output end isolator, an adjustable attenuator, a first variable gain amplifier, a detector, a linearizer, a second variable gain amplifier and a control circuit, wherein the input end isolator, the adjustable attenuator, the first variable gain amplifier, the detector, the linearizer, the second variable gain amplifier and the output end isolator are connected in series, radio frequency signals sequentially pass though the input end isolator, the adjustable attenuator, the first variable gain amplifier, the detector, the linearizer, the second variable gain amplifier and the output end isolator, and finally processed radio frequency signals are outputted. The control circuit is connected with the adjustable attenuator, the first variable gain amplifier and the linearizer. The linear channel amplifier is small in size and light in weight, is delivered to military second-generation electrical satellites, and is stable in system joint-test.

Description

The linearisation channel amplifier

Technical field

The utility model relates to a kind of linearisation channel amplifier, is applied in the linearisation travelling-wave tube amplifier or in the linearisation solid-state power amplifier.

Background technology

Linearisation channel amplifier (LCAMP) is the important component part of linearisation travelling-wave tube amplifier (LTWTA), realization possesses two kinds of mode of operations and a plurality of remote-control romote-sensing function to the correction of travelling wave tube (TWT) linearity and the system gain controlled function of LTWTA complete machine.For a long time, LTWTA is dependence on import always, introduces price and is about 500,000 Euros, and the LCAMP price accounts for 1/3 of total price.Offshore company carries out blockade on new techniques to China, can't grasp the design relevant information of introducing LCAMP.

Because the complete machine function complexity of LCAMP, internal radio frequency modular circuit quantity is many, carry out the development of this product according to the method for designing of routine, can cause the product interconnector to seem too in disorder, and the weight of product, volume will be well beyond the external product levels, increase the satellite platform burden, and then the production domesticization that can influence LTWTA substitutes.

The utility model content

Technology of the present utility model is dealt with problems and is: overcome the deficiencies in the prior art, designed a kind of linearisation channel amplifier, realized the correction of the travelling wave tube linearity and the system gain controlled function of linearisation travelling-wave tube amplifier complete machine.

Technical solution of the present utility model is:

The linearisation channel amplifier, comprise input isolator ISO, output isolator ISO, adjustable attenuator ATT, the first variable gain amplifier VGA1, wave detector DET, linearizer LIN, second variable gain amplifier VGA2 and the control circuit, input isolator ISO, adjustable attenuator ATT, the first variable gain amplifier VGA1, wave detector DET, linearizer LIN, the second variable gain amplifier VGA2 and output isolator ISO are cascaded, radiofrequency signal is passed through input isolator ISO successively, adjustable attenuator ATT, the first variable gain amplifier VGA1, wave detector DET, linearizer LIN, the second variable gain amplifier VGA2 and output isolator ISO, the radiofrequency signal that final output was handled; Control circuit connects adjustable attenuator ATT, the first variable gain amplifier VGA1 and linearizer LIN.

Described control circuit comprises power filter chip, AD chip, DA chip, fpga chip and isolating chip, external power source is given fpga chip, AD chip and DA chip power supply by the power filter chip, fpga chip is handled and sent to the AD chip with the ambient temperature analog signals that receives, the external remote control signal inputs to fpga chip by isolating chip simultaneously, and fpga chip is handled temperature signal and the remote signal that receives and passed through DA chip output control voltage signal.

Described linearizer LIN comprises coupler, adjustable attenuator, phase shifter and distortion unit, and wherein attenuator and phase shifter are formed linear branch; Distortion unit constitutes non-linear branch; Input signal enters non-linear branch and linear branch respectively through coupler, and signal reflexes to the synthetic output of coupler isolated port afterwards again through conversion in two branch roads.

The utility model beneficial effect compared with prior art is:

For a long time, the linearisation travelling-wave tube amplifier is dependence on import always, introduces price and is about 500,000 Euros, and the price of linearisation channel amplifier accounts for 1/3 of total price.Linearisation channel amplifier solution by the utility model proposes can realize the production domesticization of linearisation channel amplifier, can save a large amount of foreign exchange spendings for country, also can break away from situation under one's control.The utility model applied microwave hybrid integrated circuit (MHIC) technology realizes functional modules such as adjustable attenuator ATT, variable gain amplifier VGA, wave detector DET, linearizer LIN, and the hardware designs compactness has realized highly integrated, lightweight, low cost; Because radio-frequency module quantity is many, each modular circuit interface is many, during design with control circuit and the shared same carrier of radio circuit, simplified circuit interface, the microwave of comparing existing routine techniques development has product-derived, and dimensional weight all reduces 50% at least, reaches external like product design level, and the utility model has been applied in certain model, the system integration test stable performance.

Description of drawings

Fig. 1 is a circuit theory schematic diagram of the present utility model;

Fig. 2 is the utility model linearizer circuit theory schematic diagram;

Fig. 3 is the utility model control circuit principle schematic.

Embodiment

Below in conjunction with accompanying drawing embodiment of the present utility model is further described in detail.

In order to improve the non-linear index of satellite, various in the world communications at present, the device that navigation satellite is popular are to adopt linearisation travelling-wave tube amplifier or linearisation solid-state power amplifier, utilize the non-linear non-linear behaviour of linearizer effectively to compensate to travelling wave tube, thereby under the condition of guaranteed performance, effectively raise the real output of travelling wave tube, realize control simultaneously system gain.

Linearisation channel amplifier (LCAMP) is serially connected by input isolator ISO, adjustable attenuator ATT, the first variable gain amplifier VGA1, wave detector DET, linearizer LIN, the second variable gain amplifier VGA2 and output isolator ISO, radiofrequency signal is passed through input isolator ISO, ATT, VGA1, DET, LIN, VGA2 and output isolator ISO successively, the radiofrequency signal that final output was handled, principle schematic is seen Fig. 1.

Input/output terminal isolator ISO improves prevention at radio-frequency port return loss, to weaken and the influencing each other of external interface;

Adjustable attenuator ATT has the attenuation adjusting range of 20dB, can realize the blasting protection to linearisation channel amplifier product;

Variable gain amplifier VGA1 has the whole scope of Gain Adjustable of 30dB, and controlled circuit control realizes complete machine gain stepping;

Wave detector DET realizes the broadband detection function of power level, guarantees that power output is stable;

Linearizer LIN circuit comprises coupler, adjustable attenuator, phase shifter, distortion unit, and principle schematic is seen Fig. 2.Wherein, attenuator and phase-shifter are formed linear branch, and this branch road is only done the decay of amplitude and the adjusting of phase place to signal; Distortion unit constitutes non-linear branch, this branch road makes input signal produce nonlinear component, distortion unit can utilize the nonlinear characteristic of microwave device to realize, for example, non-linear microwave device such as diode or field effect transistor, (effect of coupler is that the road signal that will import is divided into two-way to input signal through coupler, be input to the non-linear branch and the linear branch of back respectively) enter non-linear branch and linear branch respectively, signal is through conversion in two branch roads, reflex to the synthetic output of coupler isolated port afterwards again, contain the predistortion component like this in the output signal, the realization amplitude, the expansion of phase place.The controlled circuit control of attenuator, phase shifter, fine compensation travelling wave tube non-linear;

Variable gain amplifier VGA2 has the gain-adjusted surplus of 10dB, realizes the adjusting to linearisation channel amplifier power output, to satisfy the incoming level requirement of travelling wave tube.

All kinds of radio-frequency modules (adjustable attenuator, variable-gain amplifier, wave detector), at home and abroad choose in the device handbook of each microwave device manufacturer, according to different application demand, different frequency range, select to satisfy the different components of different instructions for uses, realize each modular circuit function.

The LIN circuit that adopts microwave integrated circuit (MIC) technology to realize is encapsulated in the radio frequency shell, the assembling complete machine;

Control circuit is used the FPGA technology, set in advance the corresponding numerical tabular of a voltage in the fpga chip, during work, fpga chip is according to the temperature voltage signal and the remote control command signal that receive, find the output voltage values in the corresponding form, and export this predeterminated voltage system, i.e. output control voltage signal, realization is to adjustable attenuator ATT, the control of the first variable gain amplifier VGA1 and linearizer LIN operating voltage, external power source is given fpga chip by the power filter chip, AD chip and DA chip power supply, fpga chip is handled and sent to the AD chip with the ambient temperature analog signals that receives, the external remote control signal inputs to fpga chip by isolating chip simultaneously, fpga chip is handled temperature signal and the remote signal that receives and is passed through DA chip output control voltage signal, and principle schematic is seen Fig. 3;

Radio-frequency module (isolator ISO, adjustable attenuator ATT, variable gain amplifier VGA, wave detector DET, linearizer LIN) and the shared same carrier of control circuit;

The shared same box body of radio-frequency module and control circuit.

By above design, with Ku frequency range linearisation channel amplifier is example, adjustable attenuator adopts the ZHT4690-QAG of UMS company, variable gain amplifier adopt M the amplifier MAAMGM0003 of A-COM company, 13 DT-20 series of electricity wave detector during wave detector adopts, FPGA selects the XCV300-PQ240 of XILINX company for use, and isolator uses general isolator to get final product, and the main performance of embodiment can reach.

Test event	The external product index	The production domesticization test result
			Operating frequency	The Ku frequency range	The Ku frequency range
Bandwidth of operation	500MHz	500MHz
			Power output (dBm)	Reach 4dBm	Reach 4dBm
Gain ranging (dB)	20～50dB	20～50dB
			Gain expansion	Reach 4.5dB	Reach 4.3dB
The phase place expansion	Reach 45	Reach 45
			Gain flatness (saturated)	≤1dB	0.5dB
Group delay	≤1ns	0.5ns
			Weight	≤0.4kg	＜0.6kg

Claims

1. linearisation channel amplifier, it is characterized in that: comprise input isolator (ISO), output isolator (ISO), adjustable attenuator (ATT), first variable gain amplifier (VGA1), wave detector (DET), linearizer (LIN), second variable gain amplifier (VGA2) and control circuit, input isolator (ISO), adjustable attenuator (ATT), first variable gain amplifier (VGA1), wave detector (DET), linearizer (LIN), second variable gain amplifier (VGA2) and output isolator (ISO) are cascaded, radiofrequency signal is passed through input isolator (ISO) successively, adjustable attenuator (ATT), first variable gain amplifier (VGA1), wave detector (DET), linearizer (LIN), second variable gain amplifier (VGA2) and output isolator (ISO), the radiofrequency signal that final output was handled; Control circuit connects adjustable attenuator (ATT), first variable gain amplifier (VGA1) and linearizer (LIN).

2. linearisation channel amplifier according to claim 1, it is characterized in that: described control circuit comprises power filter chip, AD chip, DA chip, fpga chip and isolating chip, external power source is given fpga chip, AD chip and DA chip power supply by the power filter chip, fpga chip is handled and sent to the AD chip with the ambient temperature analog signals that receives, the external remote control signal inputs to fpga chip by isolating chip simultaneously, and fpga chip is handled temperature signal and the remote signal that receives and passed through DA chip output control voltage signal.

3. linearisation channel amplifier according to claim 1 is characterized in that: described linearizer LIN comprises coupler, adjustable attenuator, phase shifter and distortion unit, and wherein attenuator and phase shifter are formed linear branch; Distortion unit constitutes non-linear branch; Input signal enters non-linear branch and linear branch respectively through coupler, and signal reflexes to the synthetic output of coupler isolated port afterwards again through conversion in two branch roads.