CN205945984U - Duplexing double tunning module is kept apart in integration - Google Patents

Abstract

The utility model discloses a duplexing double tunning module is kept apart in integration relates to the digital television broadcasting technology field, and the technical scheme that utility model adopted is such: including metallic shield cover and a printed circuit board, printed circuit board welded fastening is in the metallic shield cover, the last integration of printed circuit has isolator circuit, diplexer circuit and tuner circuit, and isolator circuit, diplexer circuit are connected with the tuner circuit order, isolator circuit's input, diplexer circuit's network signal output part and tuner circuit's control end, two tunnel IF outputs end all cover from metallic shield and draw forth.

Description

A kind of integration isolation duplex double tunning module

Technical field

This utility model is related to digital TV Broadcasting Techniques field, particularly a kind of integration isolation duplex tuning module.

Background technology

In cable of cable TV transmitting procedure, may be because of wire electric leakage, loose contact, or lightning induction, high-tension electricity Source is incorporated in user family, causes receiving device to receive interference, damage even personal injury, in order to solve problems, needs In set-top box signal input external installation antenna isolator.Simultaneously for the numeral electricity using EOC or DOCSIS technical standard Depending on bi-directional set-top box, inside Set Top Box, need built-in use duplexer module and tuner module.Digital television bidirectional Set Top Box Using the connection of antenna isolator module, duplexer module and tuner module with realize principle such as Fig. 1.

Referring to Fig. 2, antenna isolator internal high-voltage isolation capacitance, to input with output ground, input signal heart yearn with defeated Go out to carry out high_voltage isolation and signal coupling between heart yearn, be in high impedance to direct current and low frequency signal, can eliminate because of input entoilage line, letter Number reception that between line and receiving device ground wire, holding wire, potential difference causes interference, it is to avoid receiving device spontaneous combustion, the danger such as on fire, Protection user's property and life security.

Antenna isolator, between input ground 1 and output ground 1, has two groups of ground connection high pressure and input ground 2 and output ground 2 between Isolation capacitance, each group of ground connection high_voltage isolation electric capacity may be formed by 1 to 5.Require for different isolation voltage, high pressure every It is divided into 500V, 1000V, 2000V or higher from electric capacity.

During the integration of three networks, for being difficult to carry out the old cell of fiber reforming, for realizing the function of online, broadcasting and TV Operator, on the basis of original CHINA RFTCOM Co Ltd, using frequency multiplexing technique, network signal and television broadcasting signal is loaded on not Same frequency, is mounted on original cable network, by cable tv coax, is transferred to customer households, realizes in family Net function.

It is radio and television users family in user side, input signal needs to first pass through a cable television duplexer, by network Signal and broadcast television signal are separated into two class outputs, and network signal enters NE and is changed into TCP/IP letter after treatment Number, the network equipment such as couple in router, switch, connects computer or mobile terminal realizes online；Broadcast television signal is accessed Set top box main, be tuned receive, demodulation, decoding be converted to standard television signal.

For meeting different application requirements, usually adopted by the technology that cable tv coax realizes family online Two kinds of standards of EOC and DOCSIS.EOC is the abbreviation of Ethernet Over Coxial, be one kind adopt coaxial cable transmit with The technical standard of too net, is issued and is used widely at home by domestic；DOCSIS also known as cable data System-Interface-Specification, It is another kind of technology by cable of cable TV high-speed transferring data, proposed by Cable Labs, by International Telecommunication Union ITU Adopt and be worldwide used widely.Two kinds of technology all employ frequency division multiplexing, are required for double using cable television Work device, meets the referred to as EOC duplexer of EOC standard, meets the referred to as DOCSIS duplexer of DOCSIS standard, two kinds of duplexers are only It is the difference of the wave filter that frequency partition is brought, ultimate principle has no difference.This patent is referred to as duplexer.

As Fig. 3, be that television carrier and the separation of network signal are realized by wave filter inside duplexer, duplexer defeated Enter signal and be divided into two-way through signal distributor, a road enters TV signal wave filter, another road enters network signal wave filter. It should be noted that when side circuit is realized, because the frequency shared by television carrier or network signal might not be continuous, two Frequency between person exists intersects, so the output of duplexer might not only have two-way, such as network signal may have 1 ~ 2 branch road Or may be more, so the two-way output signal Zhong Mei road of Fig. 3 description may comprise multiple tributary signals.

In simulation and digital television signal transmitting procedure, for improving transmission quality and efficiency of transmission, the quilt of different programs Transmission signal needs to be modulated on different channel with certain modulation system, carries out broadcast type biography in a wired or wireless manner Defeated, in user terminal receiver, then the carrier channel corresponding to the program that will need to receive, through amplification, frequency conversion, frequency-selecting filter Ripple, filters other channel carrier frequency, and corresponding channel carrier signal is transformed to the frequency specified, and to this assigned frequency（It is probably Intermediate frequency, Low Medium Frequency or zero intermediate frequency）It is demodulated, to be reduced into the signal modulated, the such as TS stream of digital television program or simulation PAL, NTSC or SECAM signal of TV.In the process, amplification, frequency conversion, frequency-selective filtering function are integrated in a radio frequency mould Realize in group, this radio frequency module is commonly referred to as high-frequency electronic tuner.

It can be seen that, the product above three module not merged in prior art, people need to buy above-mentioned three respectively Plant module, connect together.With continued reference to Fig. 1, isolator is installed on outside digital bidirectional set up box, be one independent Module, cable of cable TV of registering one's residence is plugged in the rf inputs of isolator module, by internal ground connection high_voltage isolation electric capacity, Signal high_voltage isolation electric capacity realize to the input of isolator and output ground between, between radio-frequency input signals and output signal High_voltage isolation, from the signal through high_voltage isolation of the coaxial output line output of isolator module, by coaxial cable or coaxial Adapter, accesses the television signal input end of digital television bidirectional Set Top Box, realizes register one's residence cable of cable TV and numeral High_voltage isolation on holding wire and ground wire for the TV bi-directional set-top box and signal coupling.

Duplexer module and tuner module are all built in digital television bidirectional Set Top Box, from the signal of isolator output Access duplexer module through radio frequency input coaxial connector, through signal distribution and traffic filter, be separated into television carrier With network signal and from the output of duplexer module.

The network signal of duplexer module output, inputs to the built-in network communication processing unit of Set Top Box, realizes TCP/ The unpacking of IP, error correction and Communication processing, are exported from Set Top Box with RJ45 joint, connect by external router, switch or directly Enter computer terminal, complete family online.

The TV carrier signal of duplexer module output, through joint and coaxial cable switching, inputs to tuner module, warp After filtering, amplification, frequency conversion reception, intermediate frequency amplify, from the output of tuner module, input to the solution on follow-up set-top box circuitry plate Tune, decoding circuit, are converted to standard television signal and export from Set Top Box, access television set and are watched.

There is certain defect in existing way, for example：

1）Isolator, duplexer, three independent modules of tuner and at least one coaxial cable is needed to carry out between module Connection；

2）Three individual module need to be required for single metallic shield, coaxial connector, circuit board, wherein isolator Module due to be in Set Top Box outside in addition it is also necessary to a set of plastic housing realizes personal contact's safety, three modules each individually produce, Debugging, inspection, packaging, material cost, production cost are higher；

3）Need a coaxial transit cable and corresponding cooperation joint to connect duplexer and two modules of tuner, enter one Step increased material cost and production cost；

4）Isolator module is coaxially connected between duplexer module, and between duplexer module and tuner module Coaxial transit cable and accordingly coordinate joint, increased the signal Insertion Loss of TV carrier signal, reduce signal receive sensitive Degree；

5）Isolator module, duplexer module and the tuner module independently producing, after connecting cooperation, because each The systematic error producing, checking, easily produces cooperation index bad, thus affecting whole system performance；

6）The production of three module independences, checkout procedure, and follow-up increased coaxial transit cable, joint, produced Journey is complicated, and the quality of production is difficult to be effectively controlled.

7）Can be only done the reception of road TV programme simultaneously and connect when previous number word TV set-top box it is impossible to meet simultaneously Receive the requirement of two-way TV programme.

Utility model content

Goal of the invention of the present utility model is：For above-mentioned problem, provide a kind of isolation duplex of integration Double tunning module.

The technical solution adopted in the utility model is such：Including metallic shield and a printed circuit board, described Printed circuit board is fixedly welded in metallic shield；

Isolator circuit, duplexer circuit and tuner circuit, isolator circuit, duplex are integrated with described printed circuit Device circuit and tuner circuit are linked in sequence；

The control end of the input of isolator circuit, the network signal outfan of duplexer circuit and tuner circuit, two Road medium frequency output end is drawn all from metallic shield.

Further, the input of isolator circuit is isolated form coaxial fitting；Isolated form coaxial fitting include input ground and Center signal line；

Between the input ground of isolated form coaxial fitting and metallic shield, electrical isolation is realized with dielectric, wear to input Cross metallic shield to be directly welded on printed circuit board, and by being grounded the ground wire on high_voltage isolation electric capacity and printed circuit board It is connected, the ground wire of printed circuit board is electrically connected with metallic shield；Described center signal line is welded on through metallic shield On printed circuit board, and it is connected with the input of duplexer circuit by signal high_voltage isolation electric capacity.

Further, described duplexer circuit is used for the Signal separator of input is TV carrier signal and network signal；Double The TV carrier signal outfan of work device circuit is connected with the input of tuner circuit.

Further, described tuner circuit be used for input signal be divided into two-way, and carry out respectively controllable gain amplification, Frequency conversion, intermediate frequency filtering and intermediate frequency controllable gain export after amplifying；

Described tuner circuit includes denoising filter, the first controller and the first controllable gain amplification being linked in sequence Device, the first frequency changer circuit, the first intermediate frequency digital wave filter and the first intermediate frequency controllable gain amplifier；

The outfan of denoising filter is connected with the input of the first controllable gain amplifier；First controllable gain amplifies Device, the first frequency changer circuit, the first intermediate frequency digital wave filter all have signal with the first controller and are connected；

Also include second controller and the second controllable gain amplifier being linked in sequence, the second frequency changer circuit, the second intermediate frequency Digital filter and the second intermediate frequency controllable gain amplifier；

The outfan of denoising filter is also connected with the input of the second controllable gain amplifier；Second controllable gain amplifies Device, the second frequency changer circuit, the second intermediate frequency digital wave filter all have signal with second controller and are connected；

The described control end of tuner circuit is respectively provided with signal with the first controller and second controller and is connected.

Further, described duplexer circuit includes signal distributor, TV signal wave filter and network signal wave filter；Institute The signal input part stating signal distributor is the input of duplexer；One outfan of signal distributor is filtered with TV signal The input of device connects, and another outfan is connected with the input of network signal wave filter；The output of TV signal wave filter Hold the TV carrier signal outfan for duplexer circuit；The outfan of network signal wave filter is the network letter of duplexer circuit Number outfan.

Further, crystal oscillator, the first converter, the first local oscillator and the first phaselocked loop are also included；Crystal shakes Swing device to be connected with the first controller, the first controller is used for by first phase lock control the first local oscillator operation in specified Frequency, the first local oscillator produces the local oscillated signal of assigned frequency and is transferred to the first converter, and the first converter is also Receive the signal of the first controllable gain amplifier output, the input of the outfan of the first converter and the first intermediate frequency digital wave filter End connects；

Also include the second converter, the second local oscillator and the second phaselocked loop；Crystal oscillator is with second controller even Connect, second controller is used for working in assigned frequency by second phase lock control the second local oscillator, the second local oscillations Device produces the local oscillated signal of assigned frequency and is transferred to the second converter, and the second converter also receives the second controllable gain and puts The signal of big device output, the outfan of the second converter is connected with the input of the second intermediate frequency digital wave filter.

Further, described TV signal wave filter is that multistage LC filter stage joint group becomes.

Further, described network signal wave filter has 1 tunnel ~ 3 road filter branch, and each branch road is multistage LC filter stage Joint group becomes.

Further, described ground connection high_voltage isolation electric capacity has two groups, and every group of ground connection high_voltage isolation electric capacity is by 1 ~ 5 capacitance group Become.

Due to employing technique scheme, the beneficial effects of the utility model are：

1）Only need to one group of metallic shield, one piece of PCBA circuit board, a production process, greatly reduce material cost With production, packing cost；

2）Built-in isolator, can lift safety in utilization and the capacity of resisting disturbance of Set Top Box；

3）Do not need coaxially connected between isolator and duplexer, and the co-axial connecting cable between duplexer and tuner With corresponding joint, reduce the material cost of bi-directional set-top box, decrease the loss of signal of transmitting procedure, improve receipt signal Sensitivity；

4）Greatly reduce small product size；

5）Prevent independent module design, production, connected brought systematic error, improve product quality.

6）Built-in two groups of tuner circuits, enable the work(that a bi-directional digital Set Top Box receives two-way TV programme simultaneously Energy.

Brief description

Fig. 1 is existing isolator, the connection diagram of duplexing module and tuning module.

Fig. 2 is existing isolator internal structure schematic diagram.

Fig. 3 is existing duplexer internal structure schematic diagram.

Fig. 4 is this utility model structural representation.

Specific embodiment

Below in conjunction with the accompanying drawings, this utility model is described in detail.

In order that the purpose of this utility model, technical scheme and advantage become more apparent, below in conjunction with accompanying drawing and enforcement Example, is further elaborated to this utility model.It should be appreciated that specific embodiment described herein is only in order to explain This utility model, is not used to limit this utility model.

This utility model passes through circuit optimization, devises a kind of duplexing double tunning module of integration isolation, this integrated mould Group is integrated in a metallic shield, built-in isolator, duplexer and tuner circuit, and this utility model module is installed on number Inside word TV bi-directional set-top box, it is directly welded on Set Top Box internal circuit board, its input can be directly connected to cable television Drop cable.

As shown in figure 4, this utility model includes metallic shield and a printed circuit board, such as pcb board or PCBA board, institute State printed circuit board to be fixedly welded in metallic shield；Isolator circuit, duplexer circuit are integrated with described printed circuit And tuner circuit, isolator circuit, duplexer circuit and tuner circuit are linked in sequence；The input of isolator circuit, double The control of the network signal outfan of work device circuit and tuner circuit, two-way medium frequency output end all draw from metallic shield Go out.

In one embodiment, the input of isolator circuit is isolated form coaxial fitting；Isolated form coaxial fitting includes Input ground and center signal line.

Between the input ground of isolated form coaxial fitting and metallic shield, electrical isolation is realized with dielectric, wear to input Cross metallic shield to be directly welded on printed circuit board, and by being grounded the ground wire on high_voltage isolation electric capacity and printed circuit board It is connected, the ground wire of printed circuit board is electrically connected with metallic shield；Described center signal line is welded on through metallic shield On printed circuit board, and it is connected with the input of duplexer circuit by signal high_voltage isolation electric capacity.

In another embodiment, isolated form coaxial fitting has two groups of input ground, and every group of input ground is high by one group of ground connection Pressure isolation capacitance is connected with the ground wire on printed circuit board, and every group of ground connection high_voltage isolation electric capacity includes 1 ~ 5 electric capacity.

Described duplexer circuit includes signal distributor, TV signal wave filter and network signal wave filter；Described signal The signal input part of allotter is the input of duplexer；One outfan of signal distributor is defeated with TV signal wave filter Enter end to connect, another outfan is connected with the input of network signal wave filter；The outfan of TV signal wave filter is double The TV carrier signal outfan of work device circuit；The outfan of network signal wave filter is the network signal output of duplexer circuit End.

In one embodiment, described TV signal wave filter is that multistage LC filter stage joint group becomes, described network signal Wave filter has 1 tunnel ~ 3 road filter branch, and each branch road is that multistage LC filter stage joint group becomes.

Described tuner circuit be used for the signal of input is divided into two-way, and carry out respectively controllable gain amplification, frequency conversion, in Export after frequency filtering and the amplification of intermediate frequency controllable gain.

In one embodiment, described tuner circuit includes denoising filter, controller 1 and the controlled increasing being linked in sequence Beneficial amplifier 1, frequency changer circuit 1, intermediate frequency digital wave filter 1 and intermediate frequency controllable gain amplifier 1.

The outfan of denoising filter is connected with the input of controllable gain amplifier 1；Controllable gain amplifier 1, frequency conversion Circuit 1, intermediate frequency digital wave filter 1 all have signal with controller 1 and are connected.

Tuner circuit also includes controller 2 and the controllable gain amplifier 2 being linked in sequence, frequency changer circuit 2, intermediate frequency digital Wave filter 2 and intermediate frequency controllable gain amplifier 2.

The outfan of denoising filter is also connected with the input of controllable gain amplifier 2；Controllable gain amplifier 2, change Frequency circuit 2, intermediate frequency digital wave filter 2 all have signal with controller 2 and are connected.

The described control end of tuner circuit is respectively provided with signal with controller 1 and controller 2 and is connected.The one of described control end Individual concrete form is probe-type interface, can be connected to I C bus and be communicated with extraneous control device.

Described frequency changer circuit is conventional circuit in tuner, and one embodiment includes converter 1, local oscillator 1 And phaselocked loop 1；Crystal oscillator is connected with controller 1, and controller 1 is used for controlling local oscillator 1 to work in by phaselocked loop 1 Assigned frequency, local oscillator 1 produces the local oscillated signal of assigned frequency and is transferred to converter 1, and converter 1 also receives can The signal of control gain amplifier 1 output, the signal of controllable gain amplifier 1 output that converter 1 receives is produced with local oscillator 1 The raw difference frequency of local oscillated signal simultaneously exports, and the outfan of converter 1 is connected with the input of intermediate frequency digital wave filter 1.

Also include converter 2, local oscillator 2 and phaselocked loop 2；Crystal oscillator is connected with controller 2, and controller 2 is used In controlling local oscillator 2 to work in assigned frequency by phaselocked loop 2, local oscillator 2 produces the local oscillations of assigned frequency Signal is simultaneously transferred to converter 2, converter 2 also receive controllable gain amplifier 2 output signal, the outfan of converter 2 with The input of intermediate frequency digital wave filter 2 connects.

During use, the isolated form coaxial input adapter of this utility model module is connected with cable television drop cable, through connecing The high_voltage isolation that ground high_voltage isolation electric capacity and signal high_voltage isolation electric capacity complete to register one's residence coaxial cable input signal and ground wire is high Signal transmission after pressure isolation, to signal distribution circuit and TV signal wave filter, network signal wave filter, is separated into TV Carrier signal and network signal, network signal directly exports from module, subsequently inputs to the built-in network communication of Set Top Box and processes Unit, realizes unpacking, error correction and the Communication processing of TCP/IP, is exported from Set Top Box with RJ45 joint, by external router, friendship Change planes or be directly accessed computer terminal, complete family online.

The PCB trace through module internal for the TV carrier signal, inputs to follow-up denoising filter, completes FM/WIFI etc. and does After disturbing the filtering of signal, it is divided into two-way, after amplified respectively, frequency-conversion processing, intermediate frequency filtering, intermediate frequency amplify, exports two from module Road intermediate-freuqncy signal, inputs to demodulation, decoding circuit on follow-up Set Top Box internal circuit board, is converted to standard television signal slave Top box exports, and accesses television set and is watched.

The foregoing is only preferred embodiment of the present utility model, not in order to limit this utility model, all this Any modification, equivalent and improvement made within the spirit of utility model and principle etc., should be included in this utility model Protection domain within.

Claims (9)

1. a kind of integration isolates duplexing double tunning module it is characterised in that including metallic shield and a printed circuit board, Described printed circuit board is fixedly welded in metallic shield；

Isolator circuit, duplexer circuit and tuner circuit, isolator circuit, duplexer electricity are integrated with described printed circuit Road is linked in sequence with tuner circuit；

In the control end of the input of isolator circuit, the network signal outfan of duplexer circuit and tuner circuit, two-way Frequency outfan is drawn all from metallic shield.

2. a kind of integration isolation according to claim 1 duplexing double tunning module is it is characterised in that isolator circuit Input is isolated form coaxial fitting；Isolated form coaxial fitting includes input ground and center signal line；

Between the input ground of isolated form coaxial fitting and metallic shield, electrical isolation is realized with dielectric, input ground passes through gold Belong to radome to be directly welded on printed circuit board, and by being grounded the ground wire phase on high_voltage isolation electric capacity and printed circuit board Even, the ground wire of printed circuit board and metallic shield are electrically connected；Described center signal line is welded on print through metallic shield On circuit board processed, and it is connected with the input of duplexer circuit by signal high_voltage isolation electric capacity.

3. a kind of integration isolation duplex double tunning module according to claim 1 is it is characterised in that described duplexer is electric It is TV carrier signal and network signal that road is used for the Signal separator of input；The TV carrier signal outfan of duplexer circuit It is connected with the input of tuner circuit.

4. a kind of integration isolation duplex double tunning module according to claim 1 is it is characterised in that described tuner is electric Road is used for being divided into two-way to the signal of input, and carries out controllable gain amplification, frequency conversion, intermediate frequency filtering and intermediate frequency controllable gain respectively Export after amplification；

Described tuner circuit include denoising filter, the first controller and the first controllable gain amplifier being linked in sequence, One frequency changer circuit, the first intermediate frequency digital wave filter and the first intermediate frequency controllable gain amplifier；

The outfan of denoising filter is connected with the input of the first controllable gain amplifier；First controllable gain amplifier, One frequency changer circuit, the first intermediate frequency digital wave filter all have signal with the first controller and are connected；

Also include second controller and the second controllable gain amplifier being linked in sequence, the second frequency changer circuit, the second intermediate frequency digital Wave filter and the second intermediate frequency controllable gain amplifier；

The outfan of denoising filter is also connected with the input of the second controllable gain amplifier；Second controllable gain amplifier, Second frequency changer circuit, the second intermediate frequency digital wave filter all have signal with second controller and are connected；

The described control end of tuner circuit is respectively provided with signal with the first controller and second controller and is connected.

5. a kind of integration isolation duplex double tunning module according to claim 3 is it is characterised in that described duplexer is electric Road includes signal distributor, TV signal wave filter and network signal wave filter；The signal input part of described signal distributor is The input of duplexer；One outfan of signal distributor is connected with the input of TV signal wave filter, another output End is connected with the input of network signal wave filter；The outfan of TV signal wave filter is the television carrier letter of duplexer circuit Number outfan；The outfan of network signal wave filter is the network signal outfan of duplexer circuit.

6. a kind of integration isolation duplex double tunning module according to claim 4 shakes it is characterised in that also including crystal Swing device, the first converter, the first local oscillator and the first phaselocked loop；Crystal oscillator is connected with the first controller, the first control Device processed is used for by first phase lock control the first local oscillator operation in assigned frequency, and the first local oscillator produces specifies The local oscillated signal of frequency is simultaneously transferred to the first converter, and the first converter also receives the first controllable gain amplifier output Signal, the outfan of the first converter is connected with the input of the first intermediate frequency digital wave filter；

Also include the second converter, the second local oscillator and the second phaselocked loop；Crystal oscillator is connected with second controller, the Two controllers are used for working in assigned frequency by second phase lock control the second local oscillator, and the second local oscillator produces The local oscillated signal of assigned frequency is simultaneously transferred to the second converter, and it is defeated that the second converter also receives the second controllable gain amplifier The signal going out, the outfan of the second converter is connected with the input of the second intermediate frequency digital wave filter.

7. a kind of integration duplexing double tunning module of isolation according to claim 5 is it is characterised in that described TV signal Wave filter is that multistage LC filter stage joint group becomes.

8. a kind of integration duplexing double tunning module of isolation according to claim 5 is it is characterised in that described network signal Wave filter has 1 tunnel ~ 3 road filter branch, and each branch road is that multistage LC filter stage joint group becomes.

9. a kind of integration duplexing double tunning module of isolation according to claim 2 is it is characterised in that described ground connection high pressure Isolation capacitance has two groups, and every group of ground connection high_voltage isolation electric capacity is made up of 1 ~ 5 electric capacity.