CN106291624A

CN106291624A - The radio-frequency transmitter of No. two satellite navigation system channel structures of the Big Dipper

Info

Publication number: CN106291624A
Application number: CN201510263978.1A
Authority: CN
Inventors: 唐守龙; 周帅林
Original assignee: BGMICRO ELECTRONICS Co Ltd
Current assignee: BGMICRO ELECTRONICS Co Ltd
Priority date: 2015-05-22
Filing date: 2015-05-22
Publication date: 2017-01-04

Abstract

The present invention relates to a kind of channel structure radio-frequency transmitter, it is a kind of No. two satellite navigation system radio-frequency transmitters of the Big Dipper, use the two completely self-contained reception channel circuits of set, B1/B2 or B1/B3 frequency can be received simultaneously, the analog if signal produced directly is sampled through ADC, inputs to Big Dipper baseband circuit.Each passage have employed double conversion structure, radio frequency single ended input, amplified by low-noise amplifier, by first order frequency mixer, radiofrequency signal is down-converted to the first intermediate-freuqncy signal, after filtered, it is converted to final intermediate-frequency by second level frequency mixer again, is then amplified output by the variable gain amplifier of band automatic gain control function.The advantage of receiver is: radio frequency single ended input facilitates radio-frequency match, and differential mixer can effectively suppress local oscillator leakage and power supply noise etc. to disturb signal, exports intermediate-freuqncy signal, can be easy to directly be connected with rear class adc circuit, baseband processing circuitry.

Description

The radio-frequency transmitter of No. two satellite navigation system channel structures of the Big Dipper

Technical field

The present invention relates to a kind of radio-frequency transmitter, the radio-frequency transmitter of a kind of No. two satellite navigation system channel structures of the Big Dipper.

Background technology

No. two satellite navigation systems of the Big Dipper are the GPSs of China's independent research, are and GPS of America, Russian GLONASS, one of European Union's GALILEO system the four big systems deposited.No. two system signals of the Big Dipper include tri-frequencies of B1, B2 and B3, and wherein B1, B2 are civil frequency, and B3 is military frequency.The Big Dipper chip only receiving B1 signal is mainly used in the civil navigation industry of meter accuracy, want to be accurate to decimeter grade or Centimeter Level, Big Dipper chip needs to resolve the signal of two frequencies of B1, B2 simultaneously, if B3 signal can be accepted, the precision of location and efficiency will promote further.

In order to meet proprietary application and the special industry application navigator fix requirements such as dual-use, high-acruracy survey, the Receiver Module of No. two terminals of the Big Dipper needs to be designed to channel structure, it is possible to receive B1 and B2 or B1 and B3 frequency simultaneously.Currently, No. two receivers of the Big Dipper all use discrete device to design, and cause system debug difficulty, and small product size is huge, and pole is unfavorable for carrying.And, No. two receivers of the current Big Dipper use and are mostly single-pass configuration, and use single-conversion structure, cause integrated level low, and mirror image rejection is poor.Meanwhile, Partial key chip is all to rely on external import, and cost is the highest.All of these factors taken together all hinders the development of dipper system and popularizes.Big Dipper terminal part miniaturization, chip welcomes preferably opportunity.

Current Beidou II receives chip and is mostly to use analog if signal output, is then converted by ADC, changes into digital signal, then delivers to baseband processing circuitry and process.

Summary of the invention

The technical problem to be solved is: the shortcoming existed for above prior art, a kind of No. two satellite navigation system dual pathways radio-frequency transmitters of the Big Dipper are proposed, improve the mirror image rejection of No. two satellite navigation system radio-frequency transmitters of the Big Dipper, improve chip integration, reduce power consumption, reduce peripheral circuit quantity, reduce cost so that receiver is easier to integrated chip.

The present invention solves the technical scheme of above technical problem:

No. two satellite navigation system dual pathways radio-frequency transmitters of the Big Dipper, including two independent reception passages, receive B1 and B2 or B1 and B3 frequency respectively.Because B2 and B3 frequency is close, B2 and B3 shares a passage.Each passage has independent low-noise amplifier, two mixer stages, band filter, intermediate frequency variable gain amplifier.The radio-frequency input signals of each passage first passes around the low-noise amplifier of each passage and is amplified, it is down to the first intermediate-freuqncy signal by first order frequency mixer, first intermediate-freuqncy signal inputs to variable gain amplifier after band-pass filter, downconverting to final intermediate-frequency by second level frequency mixer the most again, final intermediate-frequency is amplified through variable gain amplifier and automatic gain amplifier (AGC).

The invention have the advantage that the present invention uses dual channel receiver structure receiver, B1 and B2 or B1 and B3 frequency can be received simultaneously, reduce module volume, improve integrated level.Radio-frequency input signals uses single ended input, facilitates radio-frequency match；The output of first order frequency mixer and the input of second level frequency mixer use difference form, are conducive to suppression interference signal, and add the band filter of mirror image inhibitory action.

Accompanying drawing explanation

Fig. 1 is the receiver block diagram of the present invention.

Fig. 2 is that the application of the present invention connects block diagram.

Detailed description of the invention

Embodiment one

As seen from Figure 1, B1, B2 or B3 radio-frequency input signals is amplified respectively through the low-noise amplifier of respective passage, it is down to the first intermediate-freuqncy signal by first order frequency mixer, first intermediate-freuqncy signal inputs to second level frequency mixer after band-pass filter, downconvert to final intermediate-frequency, final intermediate-frequency is amplified through IF AGC control circuit (AGC) and variable gain amplifier again, and output is to rear class adc circuit and Big Dipper baseband processing circuitry.

Low-noise amplifier uses single ended input form, is then transformed into difference form, first order frequency mixer and second level frequency mixer and all uses difference form, can effectively suppress local oscillator leakage, power supply noise etc. to disturb signal.

From Figure 2 it can be seen that the channel structure receiver in the present invention, B1 and B2 or B1 and B3 frequency can be processed simultaneously, save a lot of peripheral circuit.The intermediate-freuqncy signal of output is directly connected to ADC and No. two baseband processing circuitries of the Big Dipper of rear class, convenient debugging, greatly reduces system power dissipation and cost.

The technical scheme that the present invention can also have other embodiment, all employings to replace on an equal basis or equivalent transformation is formed, within all falling within the scope of protection of present invention.

Claims

1. No. two satellite navigation system channel structure radio-frequency transmitters of the Big Dipper, including low-noise amplifier, first order frequency mixer, the first if bandpas filter, second level frequency mixer, intermediate frequency variable gain amplifier and agc circuit that two sets are independent, it is characterized in that: use two completely self-contained reception passages to process B1 frequency and B2 frequency or B1 frequency and B3 frequency respectively, it is greatly saved peripheral circuit, improves the integrated level of module.

2. No. two satellite navigation system channel structure radio-frequency transmitters of the Big Dipper as claimed in claim 1, it is characterised in that: low-noise amplifier uses single ended input form, output to be connected with first order frequency mixer, and two mixer stages uses differential input and output form；First order mixer output and the first if bandpas filter are connected, and then wave filter output is connected to second level frequency mixer, and frequency mixer output in the second level is connected with intermediate frequency variable gain amplifier again, and final intermediate-frequency amplifies output through intermediate frequency variable gain amplifier.

3. No. two satellite navigation system channel structure radio-frequency transmitters of the Big Dipper as claimed in claim 1, it is characterized in that: B1 frequency and B2 frequency or B1 frequency and B3 frequency radio-frequency input signals can be received simultaneously, produce respective intermediate frequency, can directly be connected with baseband processing circuitry with rear class adc circuit.