CN112234332B

CN112234332B - Radio frequency combiner

Info

Publication number: CN112234332B
Application number: CN202011103163.4A
Authority: CN
Inventors: 周超; 杨智光; 魏宇; 秦磊; 卢嘉
Original assignee: Shanghai Sanji Electronic Engineering Co ltd
Current assignee: Shanghai Sanji Electronic Engineering Co ltd
Priority date: 2020-10-15
Filing date: 2020-10-15
Publication date: 2021-05-07
Anticipated expiration: 2040-10-15
Also published as: CN112234332A

Abstract

The invention discloses a radio frequency combiner, which adopts a printed circuit board technology, adopts a high dielectric constant dielectric plate, adopts all the devices to be packaged by patches, can realize mass production by a patch mounter, has simple structure, high consistency, convenient assembly and debugging, low cost and reduced combiner size, and can be installed in a 1U case.

Description

Radio frequency combiner

Technical Field

The invention relates to the technical field of wireless communication, in particular to a radio frequency combiner.

Background

Currently, in wireless communication systems, more and more devices are used, antennas are everywhere, and the antenna pattern is deteriorated by the multi-antenna layout. Most of the prior art adopt an antenna combiner, and the antenna combiner mainly consists of a plurality of independent band-pass filters.

For example, an antenna combiner of a 350M frequency band is mainly composed of a plurality of independent band pass filters with an in-band impedance of 50 Ω and an out-of-band impedance of high impedance. However, when the frequency coverage factor (i.e. the ratio of the highest operating frequency to the lowest operating frequency) of the antenna combiner is greater than 2, the out-of-band impedance of each band-pass filter gradually changes from 50 Ω to high impedance along with the distance from the central operating frequency, and then gradually changes from high impedance to low impedance, i.e. each band-pass filter exhibits two low impedance characteristics in the whole operating frequency band, the isolation between transmission and reception becomes small, resulting in the echo and third-order intermodulation during transmission to other communication devices, and the performance of the antenna combiner is seriously degraded, or even cannot be used.

Meanwhile, various analog and digital communication devices exist in the 350M frequency band, and the same antenna is used in the same combiner, which often generates intermodulation interference, that is, in the same antenna combiner, the communication device of one port affects the communication devices of other ports during transmission, so that the devices of other ports cannot be used.

Some antenna combiners commonly used at present adopt an air cavity stripline structure, the power capacity is large, but the assembly and the debugging are complex, the production cost is high, the volume occupies 3U or 4U of cabinet space, the cabinet space is wasted, and third-order intermodulation is poor when the assembly or the debugging process is poor. At present, in another scheme commonly used, the size of the combiner is reduced by adopting a printed circuit board technology and a high-dielectric-constant dielectric plate, and the combiner is simple in structure, convenient to assemble and high in consistency. However, when the combiner device cannot achieve high isolation between transmission and reception, the isolation between the transmission and reception is generally 23dB to 27dB, and the use requirement cannot be met. The cost is very high if the silver plating technology is not used.

Therefore, it is desirable to provide a broadband combiner with low cost, simple assembly, small size, low loss, high isolation between transmission and reception (greater than 40dB), and high performance.

Disclosure of Invention

The invention aims to provide a broadband radio frequency combiner which is low in cost, simple in assembly, small in size, low in loss, large in power capacity and high in transmitting and receiving isolation (more than 40 dB).

In order to realize the purpose of the invention, the following technical scheme is provided: the schematic diagram can be seen in fig. 2.

A radio frequency combiner comprises a coupler, a detector, a control switch, a one-way isolator, a combiner module and a duplexer, wherein:

the input end of the coupler is distributed to the detector through the coupling section of the coupler, and the straight-through end of the coupler is directly communicated with the control switch;

the detector transmits a trigger signal to the control switch to enable the control switch to be switched between transmitting and receiving, the default state is a receiving state, when the transmitted trigger signal is generated, the control switch is switched to the transmitting state, the transmitting is finished, and the control switch returns to the receiving state;

the control switch is a broadband control switch with 0.02HZ-2.7GHZ, the used power is 50W, the transient switching rate is 85nS, the switch can be instantly switched between transmitting and receiving, and the control switch is switched to a TX end when the input power is more than 25 dBm;

the one-way isolator only exists in the transmitting channel, so that the out-of-band rejection performance is improved, and the return loss and the third-order intermodulation are suppressed;

the combining module comprises a transmitting combiner and a receiving power divider; the transmitting combiner combines a plurality of transmitting input ports into one path to be connected to a transmitting end of the duplexer, an input port of the receiving power divider is connected with a receiving port of the duplexer, an input signal is divided into multiple paths and is transmitted to the next stage, and the connected duplexer is used as an output end of the radio frequency combiner and is used for being connected with an antenna;

the invention adopts the printed circuit board technology, adopts a high-dielectric-constant dielectric plate, and all the devices are pasted Chip packaging, mass production can be realized by a chip mounter, so that the structure is simple, the consistency is high, the assembly and debugging are convenient, the batch production can be carried out, the cost is low, the size of the combiner is reduced, and the combiner can be installed in a 1U case. The overall structure size can be seen in figure 4

The in-band impedance of the device is 50 omega.

The control switch is used to separate the transmission from the reception for handling the transmission and reception operations, respectively.

A one-way isolator is used in a transmitting channel, and return loss and third-order intermodulation to other port equipment during transmitting are restrained.

The frequency band of the radio frequency combiner is 100Hz-2 GHz.

The number of the coupler, the detector, the control switch, the one-way isolator, the combiner module and the duplexer can be more than one, and the number is determined according to actual use requirements.

The invention adopts the printed circuit board technology, adopts the high dielectric constant dielectric plate, and the devices are all packaged by the surface mount, and mass production can be realized by the surface mount machine, so the structure is simple, the consistency is high, the assembly and debugging are convenient, the batch production can be carried out, the cost is low, the size of the combiner is reduced, and the combiner can be installed in a 1U case. The overall structure size can be seen in figure 4

Advantageous effects

1. When the radio frequency combiner is used, the same frequency band equipment connected with other ports cannot be influenced when the 1 equipment in the same frequency band is transmitted, a plurality of communication equipment in the same frequency band simultaneously use 1 antenna, the utilization rate of the antenna is increased, an antenna directional diagram cannot be deteriorated due to multi-antenna layout, and therefore the efficiency of the radio frequency combiner can be improved.

2. Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic diagram of an architecture of a radio frequency combiner according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a radio frequency combiner according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a control switch according to an embodiment of the present invention;

FIG. 4 is a schematic drawing of dimensions provided by an embodiment of the present invention;

FIG. 5 is a schematic diagram of a test connection provided by an embodiment of the present invention;

FIG. 6 is a diagram of test connections- -receive path, according to an embodiment of the present invention;

FIG. 7 is a test connection diagram- -transmit path- -of an embodiment of the invention:

FIG. 8 is a schematic diagram of a test connection according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a test connection according to an embodiment of the present invention. Detailed Description

Example 1

The specific embodiment provides a radio frequency combiner, including a plurality of couplers, a detector, a control switch, a one-way isolator, a combiner module and a duplexer, wherein:

the input ends of the plurality of couplers are a plurality of input ends, the input ends are distributed to the detectors through the coupling section samples of the couplers, and the through ends of the couplers are directly communicated with the control switch.

The detectors transmit trigger signals to the control switch to enable the control switch to be switched between transmitting and receiving, the default state is the receiving state, and when the trigger signals are transmitted, the control switch is switched to the transmitting state. The transmission is finished, the control switch returns to the receiving state,

the control switches are broadband control switches of 0.02Hz-2.7GHz, the normal use power is 50W, the peak power is 300W, the insertion loss is 0.3dB, the high receiving and transmitting isolation degree is 45dB, the transient switching rate is 85nS, the control switches can be instantly switched between transmitting and receiving, and the input power is larger than 25dBm and is switched to a TX end. The control switch has the characteristics of strong controllability, good linearity and low direct-current power consumption, and a schematic diagram can be seen in an attached figure 3.

The plurality of one-way isolators are only arranged in the transmitting channel, so that the out-of-band rejection performance is improved, and return loss and third-order intermodulation are suppressed.

The combiner module comprises a transmitting combiner and a receiving power divider; the transmitting combiner combines a plurality of transmitting input ports into one path to be connected to the transmitting end of the duplexer, the input port of the receiving power divider is connected with the receiving port of the duplexer, and the input signal is divided into multiple paths and is transmitted to the next stage. The connected duplexer is used as the output end of the radio frequency combiner and is used for connecting an antenna;

example 2

In order to provide a performance-improving implementation scheme, a radio frequency combiner is provided in the embodiments of the present invention, and the following description is made in conjunction with the accompanying drawings of the specification, where it is to be understood that the preferred embodiments described herein are only for illustrating and explaining the present invention, and are not to be used as limitations of the present invention. And the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

This embodiment provides a radio frequency combiner, as shown in fig. 1, which may include a plurality of couplers, detectors, control switches, unidirectional isolators, a combiner module, and duplexers, where:

the control switches are broadband control switches of 0.02Hz-2.7GHz, the normal use power is 50W, the peak power is 300W, the insertion loss is 0.3dB, the high receiving and transmitting isolation degree is 45dB, the transient switching rate is 85nS, the control switches can be instantly switched between transmitting and receiving, and the input power is larger than 25dBm and is switched to a TX end. The control switch has the characteristics of strong controllability, good linearity and low direct-current power consumption.

The plurality of one-way isolators are only arranged in the transmitting channel, so that the out-of-band rejection performance is improved, and the return loss and the third-order intermodulation are suppressed.

in this implementation, the following is a processing object test result parameter, and the working frequency band of the combiner of the present invention is 350-370 MHz. The practical application can also be used in other frequency bands of 100Hz-2 GHz.

TABLE 1 operating frequency

	TX	RX
			Working frequency (MHz)	351～356	361～366

TABLE 2 Single channel loss

TABLE 3 degree of isolation

	ANT1---ANT2	ANT2---ANT3	ANT3---ANT4
				Isolation (dB)	43	42	43

TABLE 4 standing wave ratio

	ANT1	ANT2	ANT3	ANT4
					Standing wave ratio	1.3	1.2	1.2	1.2

TABLE 5 parameters of the example entity

Overall test case connection can be seen in FIG. 5

In summary, by adopting the scheme provided by the embodiment of the invention, when a plurality of communication devices in the same frequency band are connected, compared with the prior art, the performance of the radio frequency combiner can be improved, and the effect is better especially for high-power and low-power communication devices in the same frequency band. And low cost, simple assembly, small volume, low loss, large power capacity, high isolation between transmitting and receiving (> 40 dB).

Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present application and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of this type are intended to be covered by the present invention.

Claims

1. The utility model provides a radio frequency combiner which characterized in that, radio frequency combiner includes coupler, wave detector, control switch, one-way isolator, combiner module and duplexer, wherein:

the control switch is a broadband control switch with 0.02Hz-2.7GHz, the used power is 50W, the transient switching rate is 85nS, the control switch can be instantly switched between transmitting and receiving, and the control switch is switched to a TX end when the input power is more than 25 dBm;

the combining module comprises a transmitting combiner and a receiving power divider; the transmitting combiner combines a plurality of transmitting input ports into one path which is connected to the transmitting end of the duplexer, the input port of the receiving power divider is connected with the receiving port of the duplexer, the input signal is divided into multiple paths and is transmitted to the next stage, and the connected duplexer is used as the output end of the radio frequency combiner and is used for being connected with an antenna.

2. The radio frequency combiner of claim 1, wherein: the control switch is used to separate the transmission from the reception for handling the transmission and reception operations, respectively.

3. The radio frequency combiner of claim 1, wherein: a one-way isolator is used in a transmitting channel, and return loss and third-order intermodulation to other port equipment during transmitting are restrained.

4. The radio frequency combiner of any of claims 1-3, wherein: the frequency band of the radio frequency combiner is 100Hz-2 GHz.

5. The radio frequency combiner of claim 1, wherein: the number of the coupler, the detector, the control switch, the one-way isolator, the combiner module and the duplexer can be more than one, and the number is determined according to actual use requirements.