CN103986488A - A High Performance LTE Channel Simulator Wideband RF Receiver - Google Patents

Abstract

The invention discloses a broadband radio frequency receiver of a high-performance LTE channel simulator. The broadband radio frequency receiver of the high-performance LTE channel simulator comprises a broadband radio-frequency power detection amplitude adjustment module, a segmentation frequency conversion filtering module, an automatic intermediate frequency level control module, an intermediate frequency demodulating module and a local oscillator module. The broadband radio frequency receiver has the advantages of being wide in frequency band, low in power dissipation, small in size, high in demodulating accuracy and suitable for the LTE channel simulator.

Description

A High Performance LTE Channel Simulator Wideband RF Receiver

technical field

The invention relates to a high-performance LTE channel simulator broadband radio frequency receiver, which belongs to microwave/millimeter wave device technology.

Background technique

"New Generation Broadband Wireless Mobile Communication Network" National Science and Technology Major Project is a major national science and technology project in order to promote the overall development of my country's communication industry, enhance the global status of my country's wireless mobile communication industry, cultivate the sustainable development ability of my country's mobile communication industry, and stimulate the innovation of my country's national industry important measure of development. TD-LTE and its evolution technology TD-LTE-Advanced, as a subsequent evolution technology of TD-SCDMA with my country's independent intellectual property rights, will further reflect my country's voice and competitiveness in the international communication field.

The wireless channel is a very complex and changeable signal physical channel. The wireless channel has unfavorable factors such as multipath fading, flat fading, and noise that affect the communication performance. These are issues that must be considered in the research of the communication system. The simulation of the channel It is an essential test process to ensure smooth communication between terminals developed by different manufacturers and system equipment provided by multiple manufacturers under the same communication protocol and system system. By developing and supporting LTE wireless channel simulators, the development cost of mobile communication equipment is saved, the flexibility of research and development is increased, and the development cycle is shortened, the overall development process of base stations and terminal equipment and the time for interconnection and intercommunication testing are reduced, and the time for field testing is reduced. , which plays a very positive role in improving and ensuring the interconnection of different systems and terminal manufacturers.

The broadband radio frequency receiver in the LTE channel simulator is a key part of the whole device. The radio frequency receiver can receive 400MHz~6GHz broadband wireless radio frequency signals. The receiver receiving power range is +15~-50dBm, and the processing bandwidth of the receiver can reach 100MHz, the phase of the receiver channel is adjusted by adjusting the phase of the local oscillator in the mixer, and it also needs to have the characteristics of low complexity and low power consumption.

Contents of the invention

Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a high-performance LTE channel simulator broadband radio frequency receiver, which can effectively reduce the complexity of the LTE channel simulator, reduce power consumption and volume, and achieve better phase Noise performance indicators.

Technical scheme: in order to achieve the above object, the technical scheme adopted in the present invention is:

Wideband radio frequency receiver is the core component of radio frequency and microwave systems, and plays a key role in communication, radar and electronic countermeasures. Its main technical indicators are receiving bandwidth, noise figure, receiving level dynamic range, processing bandwidth, etc. The high-performance LTE channel simulator broadband radio frequency receiver designed by the present invention has the characteristics of wide radio frequency input frequency band, wide processing bandwidth, small size, low power consumption, high performance, high integration, good performance indicators and the like. Specifically, it includes a broadband radio frequency power detection amplitude adjustment module, a segmented frequency conversion filter module, an intermediate frequency automatic level control module, an intermediate frequency demodulation module and a local oscillator module;

The wideband radio frequency power detection amplitude adjustment module: detects the power of the input signal: if the input signal power is greater than the threshold value, the input signal is attenuated, and then the attenuated signal is sent to the segmental frequency conversion filter module; if the input If the signal is less than or equal to the threshold, the input signal passes through directly and is sent to the segmental frequency conversion filter module;

The segmented frequency conversion filter module: the input signal is divided into frequency bands, for different frequency bands, after respective frequency conversion filter processing, all become intermediate frequency signals, and then the obtained intermediate frequency signals are sent to the intermediate frequency automatic level control module ;

The intermediate frequency automatic level control module: attenuates the level of the input signal power greater than the threshold range, and sends it to the intermediate frequency demodulation module after adjusting it within the threshold range; directly sends the level of the input signal power within the threshold range to The intermediate frequency demodulation module; amplifies the level of the input signal power less than the threshold range, and sends it to the intermediate frequency demodulation module after being adjusted within the threshold range;

Described intermediate frequency demodulation module: carry out quadrature demodulation to input signal, produce analog baseband signal, carry out data processing to the baseband part of LTE channel emulator; Insert a phase-adjustable intermediate frequency frequency synthesizer in intermediate frequency demodulation module, The phase of the input local oscillator signal can be adjusted to realize the function of adjusting the phase of the radio frequency receiving;

The local oscillator module: provides radio frequency local oscillator signals to the LTE channel simulator.

In order to achieve precise control of the phase in the radio frequency circuit, a phase shifter is usually inserted in the transceiver to achieve phase adjustment. Different phase shifter schemes have different phase shifting effects. The operating bandwidth of the analog phase shifter is relatively narrow; the operating frequency bandwidth of the digital control phase shifter can be slightly wider, but the phase shifting accuracy is not high enough, and the typical phase shifting accuracy is generally 6.25 degrees. The scheme adopted by the present invention is to insert a frequency synthesizer with adjustable intermediate frequency phase in the demodulation link. The phase adjustment precision of this frequency synthesizer can reach 2 degrees, the precision is high, and the implementation method is simple, and no need for the receiver and A complex phase-shifting circuit is inserted into the transmitter to further reduce the complexity of the frequency synthesizer in the LTE channel simulator.

Specifically, the broadband radio frequency power detection amplitude adjustment module includes a broadband directional coupler, a limiting amplifier, a broadband radio frequency numerically controlled attenuator and an amplifier connected in sequence, the input signal is input through a broadband directional coupler, a broadband radio frequency amplifier and a broadband radio frequency detector Power detection is performed on the output signal of the broadband directional coupler.

Specifically, the segmented frequency conversion filter module performs frequency band processing on the input signal of 400MHz～6GHz, and after performing respective frequency conversion filter processing for different frequency bands, all of them become 1.2GHz intermediate frequency signals, and then the obtained The 1.2GHz intermediate frequency signal is sent to the intermediate frequency automatic level control module.

Specifically, the segmented frequency conversion filtering module:

The 400-2GHz input signal first passes through the RF single-pole four-throw switch and enters the low-pass filter and the A-RF mixer in turn, and then changes the frequency of the signal to 3.2GHz; then enters the A-RF amplifier, A-RF band-pass filter, After the RF amplifier B and the RF mixer B, the frequency of the signal is changed to 1.2GHz; finally, it reaches the intermediate frequency automatic level control module through the A intermediate frequency amplifier and the intermediate frequency SPDT fast switch;

The 2-6GHz input signal first passes through the RF single-pole four-throw switch, one path is switched to the B RF band-pass filter for filtering processing of the 2-4GHz RF signal, and the other path is switched to the C RF band-pass filter for the 4-6GHz RF signal After filtering, the two signals are synthesized into a 2-6GHz RF signal that has been filtered through the RF SPDT switch, and the obtained 2-6GHz RF signal is down-mixed by the C broadband RF amplifier and the C RF mixer in turn. The radio frequency signal up to 1.2GHz, the obtained 1.2GHz radio frequency signal reaches the intermediate frequency automatic level control module through the B intermediate frequency amplifier and the intermediate frequency single pole double throw switch;

The remaining path of the RF single-pole four-throw switch is connected to a matching load.

Specifically, the intermediate frequency automatic level control module includes an intermediate frequency filter, a C intermediate frequency amplifier, an A intermediate frequency digitally controlled attenuator, a D intermediate frequency amplifier, a B intermediate frequency digitally controlled attenuator, and an E intermediate frequency amplifier.

Specifically, the local oscillator module includes an A intermediate frequency synthesizer, a radio frequency synthesizer and a B intermediate frequency synthesizer, and the radio frequency synthesizer provides local oscillator signals for the A radio frequency mixer and the C radio frequency mixer, so The A intermediate frequency synthesizer provides local oscillator signals for the B radio frequency mixer, and the B intermediate frequency synthesizer provides local oscillator signals for the intermediate frequency demodulation module.

Specifically, it also includes a single-chip microcomputer control module and a power supply module. Switch, IF single-pole double-throw switch, A IF digitally controlled attenuator, B IF digitally controlled attenuator, A IF frequency synthesizer, RF frequency synthesizer and B IF frequency synthesizer are controlled by chips.

Beneficial effects: the high-performance LTE channel simulator broadband radio frequency receiver provided by the present invention has the characteristics of frequency bandwidth, small power consumption, small size, and high demodulation accuracy, and is suitable for use in LTE channel simulators and corresponding broadband radio frequency receivers middle.

Description of drawings

Fig. 1 is the block diagram that is applied to the broadband radio frequency receiver in the LTE channel emulator provided by the present invention;

FIG. 2 is a block diagram of a specific implementation scheme of a wideband radio frequency receiver applied in an LTE channel simulator.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1 and Figure 2, it is a high-performance LTE channel simulator wideband radio frequency receiver, which is characterized in that it includes a wideband radio frequency power detection amplitude adjustment module, a segmented frequency conversion filter module, an intermediate frequency automatic level control module, and an intermediate frequency solution Tuning module, local oscillator module, single-chip microcomputer control module and power supply module; each module will be described in detail below.

The wideband radio frequency power detection amplitude adjustment module: detects the power of the input signal, and if it exceeds the receiving level range that the receiver can handle, the signal is disconnected through the single-chip microcomputer control module to protect the receiver from being damaged. Detect the power of the input signal: if the power of the input signal is greater than the threshold, the input signal will be attenuated, and then the attenuated signal will be sent to the segmental frequency conversion filter module; if the input signal is less than or equal to the threshold, the input signal will pass through directly And send to the subsection frequency conversion filtering module.

As shown in Figure 2, the broadband radio frequency power detection amplitude adjustment module includes a broadband directional coupler 1, a limiting amplifier 2, a broadband radio frequency numerically controlled attenuator 3 and an amplifier 4 connected in sequence, and the input signal is input through the broadband directional coupler 1, The broadband radio frequency amplifier 31 and the broadband radio frequency detector 32 perform power detection on the output signal of the broadband directional coupler 1 .

The segmented frequency conversion filter module: perform frequency band processing on the input signal of 400MHz～6GHz, and after performing respective frequency conversion filter processing for different frequency bands, all become 1.2GHz intermediate frequency signals, and then convert the obtained 1.2GHz The intermediate frequency signal is sent to the intermediate frequency automatic level control module.

As shown in Figure 2, the 400-2GHz input signal first passes through the RF single-pole four-throw switch 5 and enters the low-pass filter 6 and the A RF mixer 11 in turn, and then changes the frequency of the signal to 3.2GHz; then enters the A RF After the amplifier 12, the A radio frequency bandpass filter 13, the B radio frequency amplifier 14 and the B radio frequency mixer 15, the frequency of the signal is changed to 1.2 GHz; at last the intermediate frequency is automatically reached by the A intermediate frequency amplifier 16 and the intermediate frequency SPDT fast switch 20. level control module. The 2-6GHz input signal first passes through the RF single-pole four-throw switch 5, one way is switched to the B radio frequency band-pass filter 7 to filter the 2-4GHz radio frequency signal, and the other is switched to the C radio frequency band-pass filter 8 for 4-6GHz The radio frequency signals of the two channels are filtered, and the two signals are respectively synthesized into a filtered radio frequency signal of 2-6 GHz through the radio frequency single-pole double-throw switch 10, and the obtained radio frequency signal of 2-6 GHz passes through the C broadband radio frequency amplifier 17 and the C radio frequency signal successively. The mixer 18 down-mixes the radio frequency signal to 1.2 GHz, and the obtained radio frequency signal of 1.2 GHz reaches the intermediate frequency automatic level control module through the B intermediate frequency amplifier 19 and the intermediate frequency single pole double throw switch 20 . The remaining path of the RF single-pole four-throw switch 5 is connected to a matching load 9 .

The intermediate frequency automatic level control module: attenuates the level of the input signal power greater than the threshold range, and sends it to the intermediate frequency demodulation module after adjusting it within the threshold range; directly sends the level of the input signal power within the threshold range to The intermediate frequency demodulation module: amplifies the level of the input signal power less than the threshold range, and sends it to the intermediate frequency demodulation module after being adjusted within the threshold range.

As shown in Figure 2, the intermediate frequency automatic level control module includes an intermediate frequency filter 24, a C intermediate frequency amplifier 25, an A intermediate frequency numerically controlled attenuator 26, a D intermediate frequency amplifier 27, a B intermediate frequency numerically controlled attenuator 28 and an E intermediate frequency amplifier connected in sequence 29.

Described intermediate frequency demodulation module: carry out quadrature demodulation to input signal, produce analog baseband signal, carry out data processing to the baseband part of LTE channel emulator; Insert a phase-adjustable intermediate frequency frequency synthesizer in intermediate frequency demodulation module, The phase of the input local oscillator signal can be adjusted to realize the function of adjusting the phase of the radio frequency reception.

The local oscillator module: provides radio frequency local oscillator signals to the LTE channel simulator. As shown in Figure 2, the local oscillator module includes an A intermediate frequency synthesizer 22, a radio frequency synthesizer 21 and a B intermediate frequency synthesizer 23, and the radio frequency synthesizer 21 is an A radio frequency mixer 11 and a C radio frequency mixer The frequency converter 18 provides local oscillator signals, the A intermediate frequency synthesizer 22 provides local oscillator signals for the B radio frequency mixer 15, and the B intermediate frequency synthesizer 23 provides local oscillator signals for the intermediate frequency demodulation module.

The single-chip microcomputer module has a wideband radio frequency numerical control attenuator 3, a radio frequency single pole four throw switch 5, a B radio frequency bandpass filter 7, a C radio frequency bandpass filter 8, a matching module 9, a radio frequency single pole double throw switch 10, and an intermediate frequency single pole double throw The chips of the switch 20, the A intermediate frequency digital control attenuator 26, the B intermediate frequency digital control attenuator 28, the A intermediate frequency frequency synthesizer 22, the radio frequency frequency synthesizer 21 and the B intermediate frequency frequency synthesizer 23 are controlled.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also possible. It should be regarded as the protection scope of the present invention.

Claims (7)

1. a high-performance LTE channel simulator wideband radio receiver, is characterized in that: comprise broadband radio-frequency power detected amplitude adjusting module, segmentation variable-frequency filtering module, intermediate frequency automatic electric-level control module, intermediate frequency demodulation module and local oscillator module;

Described broadband radio-frequency power detected amplitude adjusting module: the power to input signal detects: if input signal power is greater than threshold value, input signal is carried out to attenuation processing, then the signal after attenuation processing is sent to segmentation variable-frequency filtering module; If input signal is less than or equal to threshold value, input signal directly by and send to segmentation variable-frequency filtering module;

Described segmentation variable-frequency filtering module: input signal is carried out to frequency-division section processing, for different frequency ranges, carry out respectively, after variable-frequency filtering processing separately, all becoming intermediate-freuqncy signal, then the intermediate-freuqncy signal obtaining is sent to intermediate frequency automatic electric-level control module;

Described intermediate frequency automatic electric-level control module: the level that input signal power is greater than to threshold range is decayed, sends to intermediate frequency demodulation module after adjusting in threshold range; Level to input signal power in threshold range, directly sends to intermediate frequency demodulation module; The level that input signal power is less than to threshold range amplifies, and sends to intermediate frequency demodulation module after adjusting in threshold range;

Described intermediate frequency demodulation module: input signal is carried out to quadrature demodulation, produce analog baseband signal, carry out data processing to the baseband portion of LTE channel simulator; In intermediate frequency demodulation module, insert an IF-FRE synthesizer that phase place is adjustable, make the local oscillation signal phase place of input adjustable, realize the adjustable function of radio frequency reception phase place;

Described local oscillator module: radio-frequency (RF) local oscillator signal is provided to LTE channel simulator.

2. high-performance LTE channel simulator wideband radio receiver according to claim 1, it is characterized in that: described broadband radio-frequency power detected amplitude adjusting module comprises braodband directional coupler (1), limiting amplifier (2), wide band radio-frequency numerical-control attenuator (3) and the amplifier (4) connecting successively, input signal is via braodband directional coupler (1) input, and wideband radio frequency amplifier (31) and wide band radio-frequency wave detector (32) carry out power detection to the output signal of braodband directional coupler (1).

3. high-performance LTE channel simulator wideband radio receiver according to claim 2, it is characterized in that: described segmentation variable-frequency filtering module, the input signal of 400MHz～6GHz is carried out to frequency-division section processing, for different frequency ranges, carry out respectively after variable-frequency filtering processing separately, all become the intermediate-freuqncy signal of 1.2GHz, then the intermediate-freuqncy signal of the 1.2GHz obtaining is sent to intermediate frequency automatic electric-level control module.

4. high-performance LTE channel simulator wideband radio receiver according to claim 3, is characterized in that: described segmentation variable-frequency filtering module:

First 400～2GHz input signal enters after low pass filter (6) and A radio-frequency (RF) mixer (11) successively by radio frequency hilted broadsword four throw switches (5), and the frequency of signal is become to 3.2GHz; And then enter successively after A radio frequency amplifier (12), A radio frequency band filter (13), B radio frequency amplifier (14) and B radio-frequency (RF) mixer (15), the frequency of signal is become to 1.2GHz; Finally by A intermediate frequency amplifier (16) and intermediate frequency single-pole double throw quick closing valve (20), arrive intermediate frequency automatic electric-level control module;

2～6GHz input signal is first by radio frequency hilted broadsword four throw switches (5), one tunnel is switched to B radio frequency band filter (7) radiofrequency signal of 2～4GHz is carried out to filtering processing, another road is switched to C radio frequency band filter (8) radiofrequency signal of 4～6GHz is carried out to filtering, two paths of signals synthesizes respectively the radiofrequency signal of a 2～6GHz who has processed after filtering by radio frequency single-pole double-throw switch (SPDT) (10), the radiofrequency signal of the 2～6GHz obtaining is passed through the radiofrequency signal that is mixed to 1.2GHz under C wideband radio frequency amplifier (17) and C radio-frequency (RF) mixer (18) successively, the radiofrequency signal of the 1.2GHz obtaining arrives intermediate frequency automatic electric-level control module by B intermediate frequency amplifier (19) and intermediate frequency single-pole double-throw switch (SPDT) (20),

The remaining road matching connection load (9) of radio frequency hilted broadsword four throw switches (5).

5. high-performance LTE channel simulator wideband radio receiver according to claim 4, is characterized in that: described intermediate frequency automatic electric-level control module comprises intermediate-frequency filter (24), C intermediate frequency amplifier (25), A intermediate frequency numerical-control attenuator (26), D intermediate frequency amplifier (27), B intermediate frequency numerical-control attenuator (28) and the E intermediate frequency amplifier (29) connecting successively.

6. high-performance LTE channel simulator wideband radio receiver according to claim 5, it is characterized in that: described local oscillator module comprises A IF-FRE synthesizer (22), rf frequency synthesizer (21) and B IF-FRE synthesizer (23), described rf frequency synthesizer (21) provides local oscillation signal for A radio-frequency (RF) mixer (11) and C radio-frequency (RF) mixer (18), described A IF-FRE synthesizer (22) provides local oscillation signal for B radio-frequency (RF) mixer (15), and described B IF-FRE synthesizer (23) provides local oscillation signal for intermediate frequency demodulation module.

7. high-performance LTE channel simulator wideband radio receiver according to claim 6, it is characterized in that: also comprise single chip control module and power module, described one-chip computer module is to wide band radio-frequency numerical-control attenuator (3), radio frequency hilted broadsword four throw switches (5), B radio frequency band filter (7), C radio frequency band filter (8), matching module (9), radio frequency single-pole double-throw switch (SPDT) (10), intermediate frequency single-pole double-throw switch (SPDT) (20), A intermediate frequency numerical-control attenuator (26), B intermediate frequency numerical-control attenuator (28), A IF-FRE synthesizer (22), the chip of rf frequency synthesizer (21) and B IF-FRE synthesizer (23) is controlled.