CN1093212A

CN1093212A - The interconnection of parts

Info

Publication number: CN1093212A
Application number: CN 93119963
Authority: CN
Inventors: K·里普斯特兰
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 1992-12-23
Filing date: 1993-12-22
Publication date: 1994-10-05
Anticipated expiration: 2013-12-22
Also published as: CN1035463C; SG49042A1; NO943081D0; EP0679299A1; SE9203903L; NO943081L; NO308720B1; FI943855A0; WO1994015410A1; SE9203903D0; FI943855A; JPH07504307A; AU5825894A; SE500713C2

Abstract

The present invention relates separately to and is used for interconnection or communicating devices and method between parts or element, these parts or element preferably are designed for radio communication, wherein have at least one be optionally with the reflection, the adjustable phase shifter of setting is corresponding adjustable between 0 ° and 180 ° with the complete break-in in the Smith chart.

Description

The interconnection of parts

The present invention relates to be used for the device of parts or element interconnection, according to the preamble of claim 1, be and be used at least two devices that preferably are designed for the component interconnect of radio communication, parts that interconnect or element are optionally with reflection.

In the example of for example radio communication; if between parts, there is not broadband isolation; interconnecting or connecting two different elements or parts; and wherein have at least one to be optionally the time; because the reflective interaction between the parts; the reflection that will have problems, and because various reason this situation occurs through regular meeting.The example of element or parts can for example be other parts of antenna, pre-filter and some kinds.

In for example very high frequency(VHF) (VHF) communication system (30-90 megahertz), transmitter and receiver can correspondingly be configured to very close to each other.This just means that transmitter must have higher selectivity, that is to say the power of no other frequency that must decay, though utilized bandwidth assignment, the power of other frequencies also can have problems.Have the required higher selectivity of above-mentioned transmitter and receiver and be accompanied by higher current drain, and higher in many cases current drain is disadvantageous, if for example under emittor/receiver is of portable form situation.Also need on possible extent, can utilize identical parts in addition.In this case, for example additional filter can be used for before the front end receiver, and be used for before the above-mentioned transmitter.The output of transmitter is included in the output of the active parts of impedance matching on the whole frequency range, therefore can not have problems.In the time of before filter being arranged on front end receiver, will have problems, this is to have the logical optionally filter of band because front end receiver comprises, and by the impedance and not all be identical on whole frequency band of this filter, this just needs outer passive filter to play the effect of the optionally band pass filter with receiver raising.Above-mentioned explanation only is for example, its objective is a field that will illustrate in a plurality of important fields.

Known interconnection system is so-called " front end " radio receiver, before the logical pre-filter of band antenna is arranged usually.This antenna is applicable to broadband signal, and this variation that just means impedance is very big.If this antenna is what is called " short whiplike " antenna of 30-88 megahertz, its standing-wave ratio (VSWR) can reach 1: 6, will become problem and be installed under the situation of VSMR on can the vehicle up to 1: 4 at antenna.According to cable length and tuned frequency, the phase place of VSWR will change, and this will influence and reduce the selectivity of system significantly.

In another kind of known system,, attempted to improve the selectivity of system by " reflection " filter outside between antenna and receiver preselector, being provided with.This design be intended that the selectivity that improves each band pass filter respectively.Yet this scheme can cause total selectivity to be lower than the selectivity of each independent band pass filter.To wherein a kind of explanation is the sub-fraction that the logical scope of band only constitutes the whole frequency range that needs the control band pass filter.The total system that causes owing to two element interconnections reduces optionally that its reason is corresponding to be to import the no control phase place that causes with the output signal reflection coefficient.Adopting optionally, its purpose of element is to obtain to the reflection of power in the stopband and the coupling in passband.Since two elements the VSWR of interconnection point with and phase place, in stopband, may produce and unwanted coupling, this can reduce selectivity, in the worst case even can lose selectivity.Known solution to this problem is that super large ground is the outer filter selected size, perhaps introduce various coefficient of safetys for the various requirement of main system, so that the selectivity by this scheme compensation reduces although therefore have all above-mentioned factors, still can satisfy the various requirement of this system.But this method generally is power consumption, and needs more expensive passive component.

According to another kind of embodiment, buffer interconnects between front end receiver and outer filter.These buffers can for example comprise amplifier or can obtain good isolator of isolating.Normal impedance on the frequency range that is intended that the corresponding at least normal frequency scope of maintenance (for example 30-90 megahertz) of this design.If yet amplifier is connected on the front end receiver, be used for the impedance variation of isolated antennas, this just needs power consumption more, also can relate to the cost problem.This scheme also can produce adverse influence to the rate of breakdown of system.Size according to when hanging down the normal system frequency also is difficult to carry out the connection of passive isolator between miscellaneous part, in order to keep the performance of system, passive isolator and amplifier also need emittor/receiver to be coupled again.Therefore this scheme is also based on the buffer that power consumption is set, and under the situation that other parts or element are introduced, will keep satisfying various requirement between miscellaneous part.For example narrowband radio equipment can be stipulated the cable length between outer filter and the receiver.Adopting under the situation of broadband radio equipment for example, need controlled cable length, i.e. phase shifter.In No. 4799066 and No. 4965607 United States Patent (USP)s, illustrated to be used to make loss to be reduced to the device of minimum degree, this loss be meant with regard to related impedance with receive/input and output and the so accurately loss between the antenna of qualification that the frequency of emission accurately limits respectively.Yet can not obtain the highest selectivity by this scheme, but can carry out the selected of optimal parameter making pass-band loss be reduced to minimum degree.The example of phase shifter has been shown in for example No. 0403176 european patent application and No. 4232399 United States Patent (USP)s.

An object of the present invention is to provide a kind of being used in radio communication for example to the device of component interconnect, these parts be optionally with the reflection, so that according to given system requirements or obtain the selectivity that to allow, need not super large ground for its no part/parts selected size, just can obtain the higher system selectivity.Another object of the present invention provides a kind of device of energy control phase, does not wherein need for example buffer of amplifier or passive isolator form between the parts, does not also need the selector of emittor/receiver.Therefore purpose of the present invention is exactly to make the interconnection between the parts can not cause system optionally to reduce.A further object of the invention is to interconnect to parts optionally, and can not make total selectivity be lower than the selectivity of each parts respectively, perhaps specifically, and total selectivity even can surpass each optionally summation.Purpose of the present invention is exactly when interconnection optionally and during the parts of (arrowband) reflection, reduces or eliminates passband and optionally reduce.

Device with technical characterictic of claim 1 characteristic promptly is provided with adjustable phase shifter between at least two parts, this adjustable phase shifter and Smith chart (Smith-Chart ^TM) in complete break-in corresponding adjustable between 0-180 °, can realize the above and other purpose.Can realize that the above-mentioned purpose method is documented in the claim 22, promptly be used for method to element or component interconnect, these elements or parts be optionally with the reflection, it is characterized in that: between the parts that will be interconnected adjustable phase shifter is set, this phase shifter is corresponding adjustable between 0-180 ° with the complete break-in in the Smith chart.Preferred embodiment has the feature of dependent claims, and for example, tuning is adaptive or automatic; Adopt so-called quiet method of counting for cable length given between the parts, carry out tuning phase shifter; Adopt so-called signal noise ratio method, carry out tuning phase shifter; Adopt so-called bit error rate (BER) method, carry out tuning phase shifter; The antenna that element that at least one will be interconnected or parts comprise The Wide-Band Design; At least one parts comprises filter; Filter comprises pre-filter; Two parts comprise filter; Filter comprises band pass filter and pre-filter, and wherein band pass filter preferably is arranged on before the pre-filter; At least two parts that will be interconnected comprise filter and transmitter; For the interconnection of three parts, be preferably antenna, band pass filter and pre-filter, comprise first and second phase shifters; At least one phase shifter is passive; At least one phase shifter is active; At least one filter is passive; At least one filter is active; The phase resolution of phase shifter is adapted to system, and depends on system; Phase place is tuning to disperse; Phase shifter has 5 ° of phase resolutions of tool; And phase place tuning be continuous.

To further specify the present invention referring to accompanying drawing below, these accompanying drawings are to be used to illustrate the present invention, rather than are used to limit the present invention.

Fig. 1 correspondingly shows the interconnection of two " reflection " element one antennas and pre-filter.

Fig. 2 shows the interconnection of antenna-outer filter-pre-filter.

Fig. 3 schematically show have the VSWR ratio be 3.5: 1 broad-band antenna with have the interconnection example of the preselector of 5 ° of phase resolutions.

Fig. 4 shows the embodiment of Fig. 3 with adding up.

Fig. 5 schematically show antenna-outer filter-preselector do not have to isolate and phase-resolved be interconnection under 5 ° the situation.

Fig. 6 with isolate the embodiment that shows Fig. 5 fully with comparing statistics.

Figure 1 illustrates the interconnection of element-antenna and the pre-filter or the band pass filter of two reflection type.Between the

element

1 and 3 of two reflections, be provided with phase shifter 2.Phase shifter 2 is corresponding adjustable between 0 ° and 180 ° with the complete break-in in the Smith chart, from this figure, can distinguish and the Smith chart phase place and the amplitude that detect for different reflection parameters, and from this figure, can further obtain corresponding synthesis of conjugate impedance.Correctly tuning by to phase shifter 2 when two elements of interconnection or

parts

1 and 3, can not produce optionally reduction.On the contrary, correct tuningly system total optionally raising or improvement can be caused, 6 decibels can be reached.Pre-filter be connected to the corresponding receiver 6 of this filter interpole on.

Figure 2 illustrates an embodiment, it was provided with outside band pass filter before the pre-filter of radio input equipment or band pass filter 3, or outer band pass filter 5.Be used for the interconnection of different elements, phase shifter (phase tuner) 4 is interconnected between pre-filter 3 and in addition logical (BP) filter 5.Then also outside before the bandpass filter, promptly between outer filter 5 and antenna 1, be provided with first phase shifter 2 '.Importantly how to

phase shifter

2,2 ' and 4 carry out tuning or control, that is to say under this concrete situation,, should get which phase position now for different receive frequencies.

According to an embodiment, can be by adopting so-called quiet method of counting to

phase shifter

2,2 ' and 4 control or tuning.Adopt this method, begin several values of element or parts reflection parameter to be measured and the phase value of tuned frequency is calculated and is stored in the look-up table beginning.And phase value is effective for a frequency of given cable length.Therefore in this table, can find the value that is used for phase shifter for tuned frequency.This method uses simply, does not still consider factors such as part aging.As mentioned above the cable with accurate qualification length must be set between outer filter and wireless device in addition.

Another kind is used for method tuning or the control phase shifter, by adopting the SNR(signal noise ratio) or the BER(bit error rate (BER)) tuned frequency, draw and can make system reach the phase value of optimum performance with adapting to.Under the help of these methods, this scheme will be irrelevant with the length of cable, so cable can be got different sizes.By adapt to the bit error that the ground coupling detects in receiver, make the phase shifter coupling then, so that make bit error be reduced to minimum degree.The tuning of phase shifter only can produce slight influence to the decay of passband, and therefore also only can produce slight influence to desired signal.

Can also phase shifter be set with some kinds of other methods, to have the continuation mode or the discrete way of low straight-through loss, preferred value is less than 1 decibel.Can't avoid the passband mismatch according to above-mentioned method.Yet the transformation ratio of suitable equivalence that can be by adaptive passband VSWR addresses this problem.But this problem with reduce optionally in stopband that to compare be unessential.

Figure 3 illustrates the influence of non-phase matched, this figure is that to have the VSWR ratio be to make under 3.5: 1 the situation of antenna being provided with before pre-filter or the band pass filter.This figure also shows 36 curves (all not illustrating in the drawings), and corresponding phase resolution is 5 ° of antenna impedances under the situation respectively, i.e. each set point of a corresponding phase shifter of curve.Certainly can adopt another kind of by phase resolution application specifies and that select in a suitable manner.That is to say that phase resolution is relevant with system, selecting phase resolution is in order to realize best systematic function.As mentioned above, can be continuous, for example be subjected to voltage control, perhaps have discrete interval, wherein 5 ° only is as illustrating.Can be more rough, also can be more accurate.Show the frequency between 47.5 megahertz to 52.5 megahertzes in an embodiment, the corresponding pass band areas of regional I, and the zone that indicates with II has marked stop band region.Article 36, the complete break-in in the curve, 36 * 5 °=180 ° corresponding Smith charts.The pass filter of illustrated curve correspondence under normal load and information source impedance situation, and be that unit shows the tuning loss that can produce of incorrect phase shifter in the drawings with the decibel, the corresponding region is b, and adopts the gain selectivity of phase shifter to be denoted as a.Antenna is a broad-band antenna in this embodiment.Can clearly be seen that from this figure compare with optionally changing, out of phase only has slight influence to pass-band loss.

Fig. 4 shows the result of Fig. 3 with adding up, wherein curve C (indicating in the drawings) is to being applied to normally loaded normal filter, the selectivity that curve d is corresponding minimum, curve e correspondence is for the average selectivity of all phase positions, and last curve f(dotted line) corresponding selectivity by the correct tuning the highest reception that obtains of phase shifter.

In Fig. 5 (relative frequency skew) show basic and the corresponding interconnection of above-mentioned Fig. 2, band pass filter outside before pre-filter or band pass filter, having.Between being provided with has the phase shifter of 5 ° of resolution.With the outer band pass filter of the curve correspondence of a sign, and the curve correspondence pre-filter that indicates with circle (0).Curve group correspondence has the phase shifter interconnection of 5 ° of resolution.Show parts (outer band pass filter and preselection filter) in this embodiment and interconnected, and between is not provided with any isolation.

In Fig. 6, between the embodiment statistics and parts that not have between the parts shown in Fig. 5 to isolate, promptly have isolation between pre-filter and the outer band pass filter, the embodiment statistics that particularly have isolation fully compare.Show the corresponding minimum selectivity of curve g in this embodiment, the corresponding average selectivity of solid line, curve i correspondence is provided with the embodiment of complete isolator between parts, and the good tuning the highest selectivity as a result that obtains of phase shifter of the corresponding response of curve j, wherein A is corresponding by adopting tuning well phase shifter, with respect to the selectivity gain that complete isolator obtains is set between parts.According to the frequency band that uses, perhaps in a frequency band, filter can be active, also can be passive, and this point is less than influence.This selection also can be used for phase shifter, that is to say that phase shifter can be active in a frequency band, also can be passive.

Embodiment shown in the present invention not only is confined to certainly, but in the protection range of claim, can optionally change.The present invention relates to all the various optionally elements of reflection and the interconnection of parts.In addition, can interconnect to several parts.Wherein phase shifter can be arranged between one or more parts.Can also carry out wherein can selecting those methods, and only having mentioned limited several method in the present disclosure with some kinds of diverse ways according to the requirement of using to the tuning of phase shifter and control.Can use one particular embodiment of the present invention and relate to the broadband high selectivity receiver that is connected on " bad " antenna, that is to say, for example owing to lacking reasons such as space, the voltage standing wave ratio of this receiver (VSWR) is relatively poor on whole frequency range.In addition, the present invention can be used among several different embodiment certainly.

Claims

1, is used at least two parts (1,3; 1,5; 3,5) Hu Lian device, these parts preferably are designed for radio communication, parts that interconnect or element be optionally with the reflection, it is characterized in that: at least two parts (1,3; 1,5; Adjustable phase shifter (2 is set 3,5); 2 '; 4), this adjustable phase shifter is corresponding adjustable between 0-180 ° with the complete break-in in the Smith chart.

2, device according to claim 1 is characterized in that: tuning is adaptive or automatic.

3, device according to claim 1 is characterized in that: adopt so-called quiet method of counting for cable length given between the parts, to phase shifter (2; 2 '; 4) carry out tuning.

4, device according to claim 1 is characterized in that: adopt so-called signal noise ratio method, to phase shifter (2; 2 '; 4) carry out tuning.

5, device according to claim 1 is characterized in that: adopt so-called bit error rate (BER) method, to phase shifter (2; 2 '; 4) carry out tuning.

6, device according to claim 1 is characterized in that: the antenna that element that at least one will be interconnected or parts comprise The Wide-Band Design.

7, device according to claim 1 is characterized in that: at least one parts comprises filter (3; 3 '; 5).

8, device according to claim 7 is characterized in that: filter comprises pre-filter (3; 3 ').

9, device according to claim 7 is characterized in that: two parts (3; ' 5) comprise filter.

10, device according to claim 9 is characterized in that: filter comprises band pass filter (5) and pre-filter (3), and wherein band pass filter (5) preferably is arranged on pre-filter (3) before.

11, device according to claim 1 is characterized in that: at least two parts that will be interconnected comprise filter and transmitter.

12, device according to claim 1 is characterized in that: for the interconnection of three parts, be preferably antenna (1), band pass filter (5) and pre-filter (3 '), comprise first (2 ') and second (4) phase shifter.

13, according to the described device of any one claim among the claim 1-12, it is characterized in that: at least one phase shifter is passive.

14, according to the described device of any one claim among the claim 1-12, it is characterized in that: at least one phase shifter is active.

15, according to the described device of any one claim among the claim 1-12, it is characterized in that: at least one filter is passive.

16, according to the described device of any one claim among the claim 1-12, it is characterized in that: at least one filter is active.

17, according to the described device of any one claim among the claim 1-12, it is characterized in that: the phase resolution of phase shifter is adapted to system, and depends on system.

18, according to the described device of any one claim among the claim 1-12, it is characterized in that: phase place is tuning to disperse.

19, according to the described device of any one claim among the claim 1-12, it is characterized in that: phase shifter has 5 ° phase resolution.

20, according to the described device of any one claim among the claim 1-12, it is characterized in that: phase place is tuning to be continuous.

21, according to the described device of any one claim among the claim 1-12, it is characterized in that: at least one phase shifter is active or passive, and at least one filter is active or passive, and phase place tuning be that disperse or continuous.

22, the method that is used for interconnection element or parts, these elements or parts be optionally with the reflection, it is characterized in that: between the parts that will be interconnected adjustable phase shifter is set, described phase shifter is corresponding adjustable between 0-180 ° with the complete break-in in the Smith chart.