CN2322267Y

CN2322267Y - Multiplex insulatio coupler for short wave antenna

Info

Publication number: CN2322267Y
Application number: CN 97231914
Authority: CN
Inventors: 张广求; 高凤玉; 李善文; 罗小武; 白贵芳
Original assignee: Information Engineering College Cp L A
Current assignee: Information Engineering College Cp L A
Priority date: 1997-12-31
Filing date: 1997-12-31
Publication date: 1999-06-02
Anticipated expiration: 2007-12-31

Abstract

The utility model relates to a multiplex insulation coupler for a short wave antenna, which is composed of more than two signal isolating coupling mechanisms whose output ends are cascaded. Each signal isolating coupling mechanism is composed of two identical transformers magic T of wideband transmission lines, two pairs of identical all-pass network phase shifters, and two identical filters. The magic T, the phase shifters, and the filters are connected orderly according to the output relation in the sequence of the magic T, the phase shifters, the filters, the phase shifters, and the magic T. Two pairs of phase shifters forms diagonal symmetry opposite to the filters. The phase difference of two phase shifters phi A, phi B of each pair of phase shifters is 90 DEG. The guard band of the utility model is narrow.

Description

Short-wave antenna multichannel isolating coupler

The utility model relates to a kind of short-wave antenna multichannel isolating coupler, especially for the antenna multichannel isolating coupler of emission.

In the prior art, have based on the multichannel isolating coupler of cutting back transmission line principle with based on the multichannel isolating coupler of trap circuit principle, because these two kinds of isolating couplers are when operating frequency changes, the tuning difficulty of coupler, only be suitable for a job frequently, the characteristics of change frequency contradict and this often needs with short wave communication, therefore in actual product, be not widely adopted, the external multichannel isolating coupler of producing that constitutes by the filter parallel connection, two frequency channels are arranged, passage be in the antenna working band than in the low-frequency range, another passage is in the higher frequency band of antenna working band, two transmitters are operated in respectively in one of them passage, and operating frequency can change arbitrarily in corresponding passage, and does not need tuning coupler.Low passage is determined by the decay of high channel filter stop bend in low passage the isolation of high channel; equally; high channel is determined by the decay of low-channel filter stopband in high channel the isolation of low passage; usually require isolation to be not less than 30dB; therefore; the interchannel interval of height promptly is to be the frequency bandwidth of 30dB from the filter passband edge to stopband attenuation, is called the protection bandwidth.As seen, the protection frequency band broad of this coupler can not make full use of the working band of antenna.

It is narrow and do not need tuning short-wave antenna multichannel isolating coupler that the purpose of this utility model provides a kind of frequency band of protecting.

For realizing this purpose, the technical solution adopted in the utility model is: a kind of short-wave antenna multichannel isolating coupler, it is formed by the cascade of plural Signal Spacing coupler output, the Signal Spacing coupler is by two identical broadband transmission-line transformer evil spirit T, two pairs of identical all-pass network phase shifter and two identical filters are formed, and by magic T, phase shifter, filter, phase shifter, the order of evil spirit T connects in turn according to output relation, two pairs of phase shifters are the diagonal symmetry with respect to filter, two phase shifter φ A of every pair of phase shifter, the phase difference of φ B is 90 °.

Phase shifter φ A is made up of inductance L a1, La2, capacitor C a1, Ca2, and phase shifter φ B is made up of inductance L b1,1b2, capacitor C b1, Cb2, the common ends ground connection of phase shifter φ A, φ B.

Each port input/output relation of evil spirit T is (referring to Fig. 1, Fig. 2), and when signal was imported from the C end, by A, the output of B two ends constant amplitude homophase, D held no-output; When signal was imported from the D end, by A, the anti-phase output of B two ends constant amplitude, C end no-output went out; Signal is from A, when B two ends constant amplitude homophase is imported, and from the synthetic output of C end, D holds no-output; Signal is during from A, the anti-phase input of B two ends constant amplitude, and from the synthetic output of D end, C holds no-output.As seen C end, D end are isolated all the time, and isolation is equal to or greater than 30dB.If signal F1 is in the passband of filter, suppose from the input of C end, then from A, the output of B two ends constant amplitude homophase, after phase shift for the first time,, arrive A ', B ' 2 points through the phase shift second time more smoothly by filter, its phase relation is constant, still is the constant amplitude homophase, therefore from the synthetic output of C ' end.If signal F2 is in the stopband of filter, and import through D ' end, then from A ', the anti-phase output of B ' two ends constant amplitude, be reflected back toward bundle through arriving filter behind the phase shifter, get back to A ', B ' through phase shifter again, promptly become the constant amplitude in-phase signal, therefore, so just realized the isolation coupling of two paths of signals also from the synthetic output of C ' end.

Because signal F1 just equals the isolation at magic TC, D two ends to the isolation of F2, the isolation that signal F2 then equals magic T to the isolation of F1 adds the stopband attenuation of filter.Therefore,, be the frequency band that do not need protection between F1 and the F2 only from guaranteeing that two paths of signals isolates, the isolation of two passages is only determined by the requirement to the loss of F2.For example; if requiring the minimum efficiency of transmission of F2 is 95%, as long as then the stopband minimal attenuation of filter reaches 13dB, like this; the protection bandwidth is to be the frequency bandwidth of 13dB from the filter passband edge to stopband attenuation, therefore boundary belt width of the present utility model.

Further specify the utility model below in conjunction with accompanying drawing and by embodiment:

Fig. 1,2 is a circuit theory schematic diagram of the present utility model.

Embodiment, short-wave antenna multichannel isolating coupler is formed by C ', D ' cascade at its output by plural Signal Spacing coupler, and the C end is signal input part.Each Signal Spacing coupler is made up of two identical broadband transmission-line transformer evil spirit T, two pairs of identical all-pass network phase shifter and two identical filters, connects in turn according to input/output relation by the order of magic T, phase shifter, filter, phase shifter, magic T.All-pass network phase shifter is made up of phase shifter φ A, φ B, phase shifter φ A is made up of inductance L a1, La2, capacitor C a1, Ca2, phase shifter φ B is made up of inductance L b1, Lb2, capacitor C b1, Cb2, capacitor C a1, Ca2 common ends ground connection, and the phase difference of φ A and φ B is 90 °.

Claims

1, a kind of short-wave antenna multichannel isolating coupler, it is characterized in that, it is formed by the cascade of plural Signal Spacing coupler output, the Signal Spacing coupler is made up of two identical broadband transmission-line transformer evil spirit T, two pairs of identical all-pass network phase shifter and two identical filters, and connect in turn according to output relation by the order of magic T, phase shifter, filter, phase shifter, magic T, two pairs of phase shifters are the diagonal symmetry with respect to filter, and the phase difference of two phase shifter φ A, φ B of every pair of phase shifter is 90 °.

2, isolating coupler as claimed in claim 1 is characterized in that, phase shifter φ A is made up of inductance L a1, La2, capacitor C a1, Ca2, and phase shifter φ B is made up of inductance L b1, Lb2, capacitor C b1, Cb2, the common ends ground connection of phase shifter φ A, φ B.