CN2315723Y

CN2315723Y - Intermodulation suppressor

Info

Publication number: CN2315723Y
Application number: CN 97245611
Authority: CN
Inventors: 扬永
Original assignee: YANGWEI ELECTRONICS SCIENCE AND TECHNOLOGY Co Ltd SHENZHEN CITY
Current assignee: YANGWEI ELECTRONICS SCIENCE AND TECHNOLOGY Co Ltd SHENZHEN CITY
Priority date: 1997-09-04
Filing date: 1997-09-04
Publication date: 1999-04-21
Anticipated expiration: 2007-09-04

Abstract

The utility model relates to an intermodulation suppressor used for suppressing the intermodulation interference signal produced by a messenger call transmitter. The utility model comprises a box body, a high Q value band pass filter 1 arranged in the box body, and a large power microwave ferrite isolator 2 arranged in the box body. One terminal of the isolator 2 is connected to one terminal of the band pass filter 1 through a cable 3. The other terminal 4 of the isolator 2 and the other terminal 6 of the band pass filter 1 are respectively connected to a transmitting antenna and the radio frequency output terminal of the transmitter. The utility model overcomes the defect that the isolator and the filter are respectively adopted for the intermodulation suppression, and has good intermodulation interference signal suppression effect.

Description

The intermodulation inhibitor

The utility model relates to the communication technology and equipment, more particularly, relates to a kind of intermodulation inhibitor that is used for mobile communication system.

The mobile communication of China development at present is very fast, and radio-paging industry especially is faster with its development, popularity rate is high and occupy first of the mobile communication development.But along with further developing of radio-paging industry, some problems also become increasingly conspicuous.Frequency range is concentrated because existing paging station uses, transmitting power is big and the transmitting antenna installation is concentrated, make and when many transmitters are worked simultaneously, just produced many Intermodulation Interference signals, these interference signals make original wireless telecommunications net operating distance descend, the situation of signal error code, error code happens occasionally, reduced the quality of communication, the serious normal radio traffic that makes can't be carried out, even whole radio communication network is paralysed.For example: on August 13rd, 97 12 noon, Shenzhen Airport air traffic control communication frequency has been subjected to the 26 interference since 97 years, be forced to close two hours, and it is reported that interference source was from radio communication transmitters a large amount of around the airport (seeing 21, Shenzhen cable TV newspaper in 97 on August).For solving the Intermodulation Interference problem, some positive explorations have all been carried out in various places at present, and currently used method has two kinds substantially.The one, serial connection one HIGH-POWERED MICROWAVES ferrite isolator (claiming isolator again) between transmitter and antenna; The 2nd, serial connection one high Q value band pass filter between transmitter and antenna.These two kinds of methods all can only play certain inhibitory action and can't eliminate Intermodulation Interference fully.At first, isolator is a kind of nonlinear device, and it also can produce high order harmonic component under the high power work state, does intermodulation with it and suppresses, and after having suppressed some interference signals, himself has produced new interference signal again; And isolator all has certain bandwidth of operation, and it is just not obvious to depart from its inhibition effect of working band; Secondly, band pass filter is a kind of reciprocal device of frequency-selecting, and it has stronger inhibition to off-center frequency interference signal far away, to a bit not suppressing effect with then having with adjacent interference signal frequently frequently.

The purpose of this utility model is to provide a kind of intermodulation inhibitor, this intermodulation inhibitor can overcome the shortcoming of prior art, can very strong inhibitory action all be arranged to all interference signals, simultaneously himself can not produce new interference signal again and influence other people, thereby solve the interference problem that exists in the present radio-paging industry preferably, reach the purpose that purifies the radio space.

The purpose of this utility model is to realize like this, construct a kind of intermodulation inhibitor that is used to suppress to notify from a phone call the Intermodulation Interference signal that transmitter produces and comprise casing, band pass filter 1 and the isolator 2 of device in casing, a terminal of isolator 2 and a terminal of band pass filter 1 join by cable 3, and the another terminal 4 of described isolator 2 and the another terminal 6 of band pass filter 1 are connected respectively to transmitting antenna and transmitter radio-frequency (RF) output end.

Intermodulation inhibitor of the present utility model is characterized in that, the requirement of described casing size conformance with standard frame dimensions is formed by panel 7 and with the U-shaped base plate 6 of panel 7 vertical connections.

Intermodulation inhibitor of the present utility model is characterized in that, described HIGH-POWERED MICROWAVES ferrite isolator 2 can be the isolator of any type, can unijunction on the structure, also can be binode or many knots, can be the lumped parameter structure, also can be the distributed constant structure.

Intermodulation inhibitor of the present utility model, it is characterized in that, the band pass filter 1 of described high Q value can be the band pass filter of any one form, as, can be screw-filter, cavity body filter and LC lumped elements filter etc., can be unijunction on the structure, also can be binode or many knots.

Implement intermodulation inhibitor of the present utility model, compared with prior art, its advantage is conspicuous: at first, all interference signals are all had inhibitory action; Secondly, can not produce new interference signal; And, versatility is good, easy for installation, use simple to operate, both can be used as an integral installation on transmitter, for example can be contained in a width be in 19 inches the standard PC case to the entire product device, also can separately be contained in the different idle position of transmitter, only needs during use this product is serially connected between transmitter and the antenna to get final product.

In conjunction with the accompanying drawings and embodiments, further specify characteristics of the present utility model, in the accompanying drawing:

Fig. 1 is the structural representation of intermodulation inhibitor of the present utility model;

Fig. 2 is the circuit theory diagrams of intermodulation inhibitor of the present utility model;

Fig. 3 is the forward characteristic curve diagram of prior art when using single isolator;

Fig. 4 is the opposite feature curve chart of prior art when using single isolator;

Fig. 5 is the indicatrix schematic diagram of prior art when using single filter;

Fig. 6 is to use the forward indicatrix schematic diagram of intermodulation inhibitor of the present utility model;

Fig. 7 is to use the opposite feature curve synoptic diagram of intermodulation inhibitor of the present utility model.

In Fig. 1, for the ease of installing and improving universal performance, intermodulation inhibitor device of the present utility model becomes a conformance with standard frame dimensions to require unit box, it comprises panel 7, U-shaped base plate 6 with panel 7 vertical connections, device has band pass filter 1 and isolator 2 on base plate 6, a terminal of isolator 2 and a terminal of band pass filter 1 join by cable 3, the another terminal 4 of described isolator 2 and the another terminal 6 of band pass filter 1 have constituted two terminals of the utility model intermodulation inhibitor, during use, one of them terminal is connected to transmitting antenna, and another terminal is connected to the transmitter radio-frequency (RF) output end.Its corresponding circuit theory diagrams as shown in Figure 2.Wherein, HIGH-POWERED MICROWAVES ferrite isolator 2 can be the isolator of any type, can be unijunction on the structure, also can be binode or many knots, and it can be the lumped parameter structure in the engineering design, also can be the distributed constant structure; The band pass filter 1 of wherein high Q value can be the band pass filter of any one form, as, can be screw-filter, cavity body filter and LC lumped elements filter etc., can unijunction on the structure, also can be binode or many knots.

Forward that Fig. 3 and Fig. 4 show prior art respectively when using single isolator and reverse characteristic curve diagram.Because isolator is a kind of nonreciprocal device, it allows working signal to pass through in certain bandwidth, and external interference signal is produced very high isolation, and it is far away more to depart from working band, and its isolation is more little; As seen from the figure, when foreign frequency overshoot scope, (oppositely) isolation effect is relatively poor, so just might make external signal externally produce interference signal by antenna again by the signal that antenna enters.

The indicatrix situation that Fig. 5 shows prior art when using single filter, because band pass filter is a kind of reciprocity frequency-selecting device, as seen from the figure, the off-center frequency is far away, its inhibition degree is bigger, center frequency point and near then do not have anything to suppress effect.

Fig. 6 and Fig. 7 show forward and the opposite feature curve that uses intermodulation inhibitor of the present utility model respectively; This intermodulation inhibitor because the advantage of two kinds of methods that prior art adopted is integrated in one, has remedied deficiency separately again mutually.In other words, by the band pass filter Combination Design with HIGH-POWERED MICROWAVES ferrite isolator and high Q value is one, the working signal of transmitter advances from the input of isolator, bring out and be connected to transmitting antenna from the output of filter, near the working frequency points of transmitter reaches mainly is to work by isolator, after departing from working band, the effect of isolator diminishes gradually, and the filter effect strengthens gradually, and, filter has also curbed the high order harmonic component that isolator produced, and makes it to be unlikely to launch, and contiguous communication apparatus is constituted new interference.To all external interference signals, the intermodulation inhibitor all can have very high inhibition, and what guaranteed that transmitting antenna sends is a purer radio signal.Compare with the method for the band pass filter of prior art single use HIGH-POWERED MICROWAVES ferrite isolator or the high Q value of single use, it is conspicuous that the utility model provides the advantage of intermodulation inhibitor.All there is being the inhibiting while can not produce new interference signal to all interference signals.And, in structural design, notice that its structure is general and aesthetic in appearance, easy for installation, use simple to operate, the entire product device can be installed on the frame of transmitter in a width is 19 inches standard PC case very easily, only needs during use it is serially connected between transmitter and the antenna to get final product.That is: the output of transmitter and intermodulation inhibitor input of the present utility model link, and its output and transmitting antenna link.

Claims

1. intermodulation inhibitor that is used to suppress to notify from a phone call the Intermodulation Interference signal that transmitter produces, it is characterized in that being connected in series by HIGH-POWERED MICROWAVES ferrite isolator 2 and high Q value band pass filter 1 forms.

2. intermodulation inhibitor according to claim 1, it is characterized in that, also comprise casing, described high Q value band pass filter 1 and HIGH-POWERED MICROWAVES ferrite isolator 2 place in the described casing, the requirement of described casing size conformance with standard frame dimensions is formed by panel 7 and with the U-shaped base plate 6 of panel 7 vertical connections.

3. intermodulation inhibitor according to claim 1, it is characterized in that, a terminal of described isolator 2 and a terminal of band pass filter 1 join by cable 3, and the another terminal 4 of described isolator 2 and the another terminal 6 of band pass filter 1 are connected respectively to transmitting antenna and transmitter radio-frequency (RF) output end.

4. intermodulation inhibitor according to claim 1 is characterized in that, described HIGH-POWERED MICROWAVES ferrite isolator 2 can be the isolator of any type, can unijunction on the structure, also can be binode or many knots, can be the lumped parameter structure, also can be the distributed constant structure.

5. intermodulation inhibitor according to claim 1, it is characterized in that, the band pass filter 1 of described high Q value can be the band pass filter of any one form, as being screw-filter, cavity body filter and LC lumped elements filter etc., can be unijunction on the structure, also can be binode or many knots.