CN205622607U - Wide frequency range's electrically tunable filter - Google Patents

Abstract

The utility model discloses a wide frequency range's electrically tunable filter, include according to the three wave filter unit of frequency sectionalised, connect in each wave filter unit the LC tuned cell to transfer resonance circuit's variable reactance component group rather than constituteing the LC electricity together, the DC power supply of wave band control circuit power supply and the direct current control source (high -low level) that is used for selections, each wave filter unit adopt and lump LC filter circuit, through required frequency signal in the section of the harmonious production to variable reactance component group " C ", realize simultaneous tuning wave filter function. The utility model discloses the wave filter adopts the piggyback control, and flexible and varied, the controllable frequency range of control mode extends, just can control voltage adjustment outward according to the difference. The high Q value varactor of variable reactance component use is regulated and control in a flexible way, uses the good inductance coils of temperature characteristic, makes the excellent performance of wave filter own, has the characteristics of undershoot damage, the interior fluctuation of low strap, high signal selection nature, and is simultaneously small, is applicable to the demand of miniaturized product.

Description

A kind of electrically tunable filter of wide frequency ranges

Technical field

This utility model relates to microwave, radio-frequency filter electronic technology field, particularly relates to a kind of broadband The electrically tunable filter of scope.

Background technology

In telecommunication technology, wave filter is to apply a special kind of skill the most widely.The telecommunication equipment in modern age and All kinds of control systems, use the parts most, technology is the most complicated to surely belong to wave filter.Therefore, filtering technique Development, the quality of performance of filter be related to the development of whole telecommunication technology.

Wave filter is the critical component in electronic system, has been used for the selection function of frequency, has mainly applied In separating signal, suppression interference.Namely allow certain band frequency signal to pass through, and suppress remaining frequency Rate section.Current communication system, not only requires wave filter filter with low insertion loss, low passband fluctuation, high signal behavior Property, and requiring that wave filter has wide frequency tuning range, good temperature characterisitic, volume is as far as possible simultaneously Little, in order to meet the requirement of communication system high-performance, miniaturization.The volume that electrically tunable filter has is little, Working band width, the advantage of flexible design, and several electrically tunable filters are integrated on a device, Broadening frequency tuning range, reduces volume, will have more the market competitiveness.

Utility model content

The purpose of this utility model is to solve shortcoming present in prior art, and propose a kind of wide The electrically tunable filter of frequency range.

To achieve these goals, this utility model adopts the technical scheme that

The electrically tunable filter of a kind of wide frequency ranges, controls including input wave band control circuit, output wave band Circuit and control power supply DC, the outfan of described control power supply DC respectively with variable reactive element group one, can The input electrical connection of variable reactive element group two and variable reactive element group three, described input wave band controls electricity The outfan on road enters with RF respectively, filter circuit, wave band control power supply DC, filter cell one, filtering The input electrical connection of device unit two and filter cell three, the input of described filter circuit and power supply DC Outfan electrically connect, the input of described output wave band control circuit respectively with filter cell one, filtering Device unit two, filter cell three, filter circuit and wave band control the outfan of power supply DC and are electrically connected with, The input of described filter circuit is electrically connected with the outfan of power supply DC, described variable reactive element group two Outfan electrically connect with the input of filter cell two, described filter cell use lump LC filtering Device circuit, the inductance in described lump LC filter circuit is Q-value height, the magnetic ring coil of good temp characteristic, And electric capacity is the varactor group that Q-value is high, the linearity is good, described variable reactive element group is that paster becomes Hold the composition LC electric tuning that is in parallel of inductance in diode, and variable reactive element group and filter cell to shake electricity Road, described input wave band control circuit is four to select an electrical switch or switching diode to lead to small size eight The combination of road bridge driver, described outfan wave band control circuit is four to select an electrical switch or switch two poles Pipe combines with small size eight passage bridge driver.

Preferably, in described filter cell, LC tuned cell therewith forms LC electric tuning and shakes circuit Variable reactive element group.

Preferably, described LC electric tuning shake DC control supply that circuit powers for individually point three tunnels to three Filter cell is powered or directly controls three filter cells with a road power supply.

Preferably, the DC source that described input/output terminal wave band control circuit is powered all has filter circuit.

Preferably, described filter circuit is electric capacity, inductor filter circuit.

Preferably, described DC control supply is low level 0～0.8V and high level 2～5V.

In this utility model, ensureing under the conditions of technical performance, it is achieved that wave filter integrated, reducing Volume.Filter internal use Discrete control, control mode is flexible and varied, controllable frequency wide ranges, And can be adjusted according to different external control voltages.Variable reactive element uses high q-factor varactor, regulation and control spirit Live, use the inductance coil of good temp characteristic, make the function admirable of wave filter own, there is filter with low insertion loss, low Passband fluctuation, the feature of high signal-selectivity, it is adaptable to the demand of miniaturized products.

Accompanying drawing explanation

Fig. 1 is structure connection diagram of the present utility model；

Fig. 2 is filter cell circuit diagram of the present utility model；

Fig. 3 is control circuit electronic switch structure circuit diagram of the present utility model；

Fig. 4 is control circuit switching diode mode circuit diagram of the present utility model；

Fig. 5 is that electric tuning of the present utility model is shaken circuit diagram.

Detailed description of the invention

Below in conjunction with accompanying drawing of the present utility model, the technical scheme in this utility model embodiment is carried out Clearly and completely describe.

With reference to Fig. 1-5, the electrically tunable filter of a kind of wide frequency ranges, including input wave band control circuit, defeated Go out wave band control circuit and control power supply DC, it is characterised in that control power supply DC outfan respectively with can The input electrical connection of variable reactive element group one, variable reactive element group two and variable reactive element group three, The outfan of input wave band control circuit enters with RF respectively, filter circuit, wave band control power supply DC, filtering The input electrical connection of device unit one, filter cell two and filter cell three, the input of filter circuit End electrically connect with power supply DC outfan, export wave band control circuit input respectively with filter cell one, Filter cell two, filter cell three, filter circuit and wave band control the outfan of power supply DC and electrically connect Connecing, the outfan of the input of filter circuit and power supply DC is electrically connected with, variable reactive element group two defeated Going out end to electrically connect with the input of filter cell two, filter cell uses lump LC filter circuit, Inductance in lump LC filter circuit is that Q-value is high, the magnetic ring coil of good temp characteristic, and electric capacity be Q The varactor group that value is high, the linearity is good, variable reactive element group is paster varactor, and can In variable reactive element group and filter cell, the inductance composition LC electric tuning that is in parallel is shaken circuit, input wave band Control circuit is four to select an electrical switch or switching diode to combine with small size eight passage bridge driver, Outfan wave band control circuit is four to select an electrical switch or switching diode to drive with small size eight passage electric bridge Dynamic device combination, in filter cell, LC tuned cell therewith forms LC electric tuning and shakes the variable of circuit Reactance component group, LC electric tuning shake DC control supply that circuit powers for individually point three tunnels to three filtering Device unit is powered or directly controls three filter cells with a road power supply, and input/output terminal wave band controls electricity The DC source that road powers all has filter circuit, and filter circuit is electric capacity, inductor filter circuit, direct current control Power supply processed is low level 0～0.8V and high level 2～5V.This utility model wave filter uses Discrete control, Control mode is flexible and varied, controllable frequency wide ranges and can being adjusted according to different external control voltages.Can Variable reactive element uses high q-factor varactor, and regulation and control flexibly, use the inductance coil of good temp characteristic, make The function admirable of wave filter own, has filter with low insertion loss, low passband fluctuation, the feature of high signal-selectivity, with Shi Tiji is little, it is adaptable to the demand of miniaturized products.

The each filter cell of this utility model has accessed variable reactive element group, is changed by VT Variable reactance " C " value becoming wave filter LC loop changes filter frequencies, reaches the purpose of electricity tune. In design, variable reactive element is made up of several varactors.

Described wave band control circuit has multiple control modes, can set according to the demand of communication device interface Meter.This utility model have employed two kinds therein, and a kind of is exactly that conventional four select an electrical switch mode, Filter cell input/output terminal all uses, synchronous working, and design is simple, but the access of electrical switch, (1～1.5) dB to drop in the Insertion Loss of wave filter.Another mode is to use switching diode, input, Output termination switching diode positive pole, utilizes DC source to gate all filter cells, eight passage electric bridges Driver connects switching diode negative pole, utilizes the low level of passage to gate a certain road, makes signal pass through.This The mode of kind does not affect the performance of wave filter own, but circuit is complicated, cost high

This utility model is made up of three electrically tunable filters worked independently.Each filter cell completes oneself The function of frequency range in segmentation.The segmentation of whole wave filter is the requirement according to equipment and external electrical tune electricity Pressure scope and determine.This utility model frequency range 1.6MHz～30MHz, electricity adjust voltage 12V or 14V, divides three sections, i.e. (1.6～4) MHz, (4～10) MHz, (10～30) MHz.

The electrically tunable filter integrated result of this utility model wide frequency ranges is good, and volume is little, only 40mm ×30mm×8mm.Its main performance all reaches to design requirement, controls simple, frequency tuning range width, Broad application temperature range, stable and reliable in work, meet the supporting demand of communication equipment, also can make small-sized simultaneously Change series of products more perfect.

The above, only this utility model preferably detailed description of the invention, but protection domain of the present utility model It is not limited thereto, the technology model that any those familiar with the art discloses at this utility model In enclosing, conceive in addition equivalent or change according to the technical solution of the utility model and utility model thereof, All should contain within protection domain of the present utility model.

Claims (6)

1. null1. the electrically tunable filter of a wide frequency ranges，Including input wave band control circuit、Output wave band control circuit and control power supply DC，It is characterized in that，The outfan of described control power supply DC respectively with variable reactive element group one、The input electrical connection of variable reactive element group two and variable reactive element group three，The outfan of described input wave band control circuit enters with RF respectively、Filter circuit、Wave band controls power supply DC、Filter cell one、The input electrical connection of filter cell two and filter cell three，The input of described filter circuit electrically connects with power supply DC outfan，The input of described output wave band control circuit respectively with filter cell one、Filter cell two、Filter cell three、Filter circuit and wave band control the outfan of power supply DC and are electrically connected with，The input of described filter circuit is electrically connected with the outfan of power supply DC，The outfan of described variable reactive element group two electrically connects with the input of filter cell two，Described filter cell uses lump LC filter circuit，Inductance in described lump LC filter circuit is that Q-value is high、The magnetic ring coil of good temp characteristic，And electric capacity is that Q-value is high、The varactor group that the linearity is good，Described variable reactive element group is paster varactor，And the inductance composition LC electric tuning that is in parallel is shaken circuit in variable reactive element group and filter cell，Described input wave band control circuit is four to select an electrical switch or switching diode to combine with small size eight passage bridge driver，Described outfan wave band control circuit is four to select an electrical switch or switching diode to combine with small size eight passage bridge driver.
2. The electrically tunable filter of a kind of wide frequency ranges, it is characterised in that in described filter cell, LC tuned cell therewith forms LC electric tuning and shakes the variable reactive element group of circuit.
3. The electrically tunable filter of a kind of wide frequency ranges, it is characterised in that three filter cells are powered or directly with road power supply three filter cells of control by the described LC electric tuning DC control supply that circuit powers that shakes for individually point three tunnels.
4. The electrically tunable filter of a kind of wide frequency ranges, it is characterised in that the DC source that described input/output terminal wave band control circuit is powered all has filter circuit.
5. The electrically tunable filter of a kind of wide frequency ranges, it is characterised in that described filter circuit is electric capacity, inductor filter circuit.
6. The electrically tunable filter of a kind of wide frequency ranges, it is characterised in that described DC control supply is low level 0～0.8V and high level 2～5V.