CN101242457B - Realization method for virtual city call commentator - Google Patents

Abstract

The invention relates to a virtual local calls adapter and the implementation method thereof, belonging to the field of Internet voice communication technology. The adapter is characterized in that: the adapter comprises a subscriber line interface circuit, a local call line interface circuit, a data control circuit, an Ethernet interface and a power supply. The data control circuit is used for control of the above circuits and human-computer interaction interface, quantifying and coding of voice signals, compressing of voice data, packing IP packet, and providing Ethernet interface. The implementation ways are mainly virtual local call calling mode and local call roaming function. Point-to-Point direct calling mode and common local adapting mode can also be realized. The invention has the characteristics of simple adapting equipment, low cost, multiple communication modes, simple usage, a local call subscriber line is unlimited extended by Internet, and all functions of IP telephone are realized.

Description

The implementation method of virtual city call commentator

The application is dividing an application of following application:

The applying date: on November 14th, 2003; Application number: 200310113531.3;

Denomination of invention: virtual city call commentator and its implementation

Technical field

The implementation method of virtual city call commentator belongs to the internet speech communication technical field.

Background technology

IP telephony technology attains full development now, and voice compressed encoding and decoding technology wherein (as H.723.1), real time transport protocol (RTP:Real-time Transport Protocol), resource reservation protocol (RSVP:Resource ReservationProtocol), call setup and control protocol are H.323, SIP etc. is quite ripe.

Carrying out voice communication (being IP phone) mode by the Internet now has: computer-computer, plain old telephone-plain old telephone, computer-plain old telephone, ether telephone set-ether telephone set, ether telephone set--plain old telephone etc.Wherein the conversation of computer-intercomputer is based upon on the hardware foundation of sound card, network interface card, uses IP telephony application (as NetMeeting) to realize compress speech and communication protocol (as H.323).Conversation between plain old telephone-plain old telephone generally is to realize the voice signal of local telephone is converted to the IP packet by the IP phone gateway of telephone office, transmits by Internet.Conversation principle between computer-plain old telephone is the combination of front dual mode, plain old telephone inserts Internet by the IP phone gateway of telephone office, at the network interface card of other end access computer, the IP phone software of computer is finished the processing of packet, thereby realizes the IP phone function.The principle of conversing between conversation basic principle between ether telephone set-ether telephone set and two computers is similar, just the IP phone function with computer is simplified on the autonomous device, and adopt twisted-pair feeder to connect Ethernet, enter into Internet by Ethernet.

Therefore, on market, there are many IP telephony products at present: products such as IP phone software terminal (as netmeeting), ether phone, IP phone gateway, gatekeeper.Though at present these products respectively have characteristics, these products all have common feature, be mainly reflected in following some:

1. these products all are to develop according to relevant international standard (as: H.323, SIP), all are to move under the certain standard system therefore.

2. these products are to move according to the IP telephony system signaling, and therefore exchange and the management system of oneself arranged.

3. all follow relevant international standard owing to these IP products, but the diversity of these standards and complexity cause the interoperability of the IP telephony product of developing in the market difficult especially.

Summary of the invention

The object of the invention is to provide a kind of local telephone network that not only can make to carry out IP communication and but also the implementation method of virtual city call commentator simple in structure, with low cost through the Internet.

The present invention proposes a kind of implementation method of IP Telephone product, this product is a kind of based on the Internet " virtual city call commentator " (being called for short " adapter ").Its basic thought is to come the relaying local telephone by the Internet, thereby covers the wide characteristics in region by the Internet, a certain local telephone network can be connected distance and extend to global range, thereby can realize that local telephone network (with the local telephone network rate) roams in the world.Simultaneously more all right expanded functions, direct calling, voice mail, mobile phone short message etc.Therefore product has following characteristics:

1. the target of equipment is just extended the line length of certain local telephone network, self does not constitute exchange and management system, and it still relies on the exchange of PSTN and management system to move, and using in connection does not need other optional equipments.

2. can be with the connection extended distance of certain road local telephone network to global range, and the telephone expenses still rate of local telephone network almost.

3. the use of its incoming call and exhalation mode and common local telephone network is without any difference, thereby can realize what is called " virtual local telephone " function.

4. equipment volume is little, use is simple, and it is convenient to insert, and can connect the Internet in the world, realizes the roaming in the world of certain local telephone network.

5. the use proprietary protocol can reduce protocol overhead, improves bandwidth utilization.

6. powerful, but cost is very low, ratio of performance to price height.

Though some is similar on basic fundamental for adapter and traditional IP phone equipment (as IP phone gateway, ether phone), is essentially different on implementation method, function and using method:

1. what adapter proposed is a kind of brand-new ip voice communication occupation mode.The comprehensive PSTN network exchange of this mode signaling system complete sum the Internet covers the wide characteristics in region, it can make full use of the function of exchange of pstn signaling system on the one hand and finish telephone connection and calling, the wide characteristics of internet data transmission range have also been made full use of on the other hand, the extension of certain local telephone network is specifically almost infinitely enlarged, and can realize global roaming.Although can adopt " IP phone gateway " that common phone also can be linked into the Internet at present, but, " IP phone gateway " is to be used for connecting two different networks of PSTN and the Internet, need finish between two networks complicated signaling format conversion, be interconnect equipment between a kind of net of upper-layer protocol; And " city call commentator " that this patent proposed just extends a certain local user's linear distance by the internet data transfer function, realize the calling of phone by the function of exchange of PSTN, therefore need not " IP phone gateway " complicated signaling system, its exchange process is to be finished by the PSTN system.Therefore, " city call commentator " can be interpreted as it is to be used for connecting two " network segment " physical layer connection devices.Therefore " city call commentator " is structurally simple many, will be low on manufacturing cost many, but approaching with " IP phone gateway " in linkage function.

2. also different ether phones of adapter.The ether phone is a kind of end equipment, and it can only realize two point-to-point calls between the ether phone, otherwise must be by setting up switch system with other equipment (as gateway and gatekeeper) of IP telephony system.

The implementation method of virtual city call commentator is characterized in that: the local telephone network roam mode of virtual city call commentator is a kind of mode of operation that can be transferred to the calling from local telephone the called adapter of acquiescence, and its job step is as follows:

Step (1) makes up virtual city call commentator, contains:

Step (1.1). Subscriber Line Interface Circuit XS is used for directly connecting Tip pin, the Ring pin of subsets;

Step (1.2). local line interface circuit XO, contain:

The speech transmissions interface chip, its end links to each other with the Ring pin of local telephone, this interface chip also has I/O Tx, the Rx of voice, ring detecting circuit one end links to each other with local telephone Tip pin through relay contact C3 when user's on-hook, this end does not link to each other with the B2 point of speech transmissions interface chip through another electric shock of relay C2 when user's off-hook is called out again, and it is A2 that the ring of this ring detecting circuit detects output;

Step (1.3). relay, coil is controlled by following data control circuit through a C1;

Step (1.4). dual-tone multifrequency is the dtmf dialing device, and output D1 links to each other with the signal input part B3 of top speech transmissions interface chip, and its input has two, is respectively dial the number input D2 and dialing signal input end D3;

Step (1.5). data control circuit, contain:

Multiway analog switch, phonetic entry end (1), speech output end (1), off-hook detection signal input part, the ring control signal output ends successively respectively with the speech output end of user interface circuit, the phonetic entry end, the output of off-hook detection signal, the ring signal input end links to each other; Phonetic entry end (2), speech output end (2), the dialing control signal output ends, ring detection signal input then successively respectively with the speech output end of local telephone network interface line, the phonetic entry end, the output of the input ring detection signal of dialing control signal links to each other; The input of dialing control signal then links to each other with the some C1 on the above-mentioned relay coil;

Step (1.6) .PCM coder, interconnected with above-mentioned multiway analog switch;

Step (1.7). the single-chip microcomputer of band LCD display, with above-mentioned PCM decoder interconnection;

Step (1.8). the Ethernet interface chip, it and above-mentioned PCM coder interconnect;

Step (1.9). power supply is respectively with above-mentioned user interface circuit XS, local line interface circuit XO, data control circuit and Ethernet interface power supply,

A digital signal processor DSP is arranged in above-mentioned data control circuit, respectively with above-mentioned PCM coder, Ethernet interface chip and single-chip microcomputer interconnection,

Described Subscriber Line Interface Circuit XS is chip MH8612C,

Digital signal processor DSP in the described data control circuit is chip TMS320C5402,

Described Ethernet interface chip is RTL8019AS,

Single-chip microcomputer in the described data control circuit is AT89C510,

Described power supply is by the AC-DC transformer of the AC220V-DC12V that links to each other with external circuits and the decompression transformation chip 7805 that links to each other with this transformer output, 5V--5V voltage reversal chip IC L7600,5V-1.8V decompression transformation chip TPS76918 and 5-3.3V decompression transformation chip TPS76933.

Step (2) makes the control circuit of adapter link to each other with the local line interface circuit, and subscriber phone and local telephone disconnect;

Step (3) is just sent a positive ring detection signal to data control circuit after the ring detecting circuit in the local line interface circuit detects from the ring of local telephone network stream signal;

Step (4) data control circuit just sends " ring signaling " by the Internet to an adapter of giving tacit consent to and be positioned at the callee in other places;

Step (5) callee's adapter is according to self state or ring loopback " user hurry signaling ";

Step (6) is in case user's off-hook of callee's adapter, the just calling party of roaming with the form notice of off-hook signaling entirely;

The adapter at step (7) roaming call user place starts Voice-Send and Voice-Receive thread, then drives relay and connects telephone wire and voice transfer interface, sets up voice-grade channel;

Step (8) roamer just can set up talking state by this adapter and nonlocal callee's adapter.

It has realized making local telephone network can carry out the purpose of telecommunication, switching, roaming by the Internet with simple equipment, cheap cost to use proof.

Description of drawings

Fig. 1. the use connected mode of adapter.

Fig. 2. the city call commentator schematic diagram.

Fig. 3. the schematic block circuit diagram of adapter.

Fig. 4. telephone set current loop figure.

Fig. 5 .MH88612C circuit connection diagram.

Fig. 6. the local line interface circuit block diagram.

Fig. 7. the schematic block circuit diagram of data control circuit and Ethernet interface.

Fig. 8 .-48V power supply wiring figure.

Fig. 9. the calling schematic diagram under the general telephone mode.

Figure 10. the annexation figure under the virtual local telephone call model.

The pattern of Figure 11 .IP phone Ethernet and the equivalent schematic of plain old telephone.

Embodiment

Conversation between realization A, B two places needs the adapter of two equities: adapter A and adapter B.Connected mode when realizing virtual local telephone communication is as shown in Figure 1: adapter has only 3 interfaces.These 3 interface functions as shown in Figure 2.

(1) block diagram of adapter as shown in Figure 3, it has five fractions, sees Fig. 3:

Subscriber line interface (XS) circuit.This circuit provides the interface of subsets.The telephone set joint has only bipod: Tip and Ring, constitute a current loop with switch output, thus transmission of analogue signal, as shown in Figure 4:

The subscriber line interface module of adapter just is equivalent to the subscriber line interface module of switch, is responsible for to the telephone wire feed, presents ring stream, and detect user's off-hook, on-hook.Tip, Ring both end voltage V during the telephone set on-hook _TRAbout 48V, V during off-hook _TRAbout 8V.Ring stream signaling is the 90V25Hz AC signal, and this signal is by telephone set identification back ring.

SLIC subscriber line interface chip has a variety of, and for example MH88500, MH88612, MC3419, MT91610, HC5503PRC etc. compare through market survey and performance, and we have selected the MH88612C chip.Its performance characteristics is as follows:

Input whole impedance 200W+560W//0.1mF.

Need not transformer and realize of the conversion of 2 lines to 4 lines.

Power supply and shake fluid line road.

On-hook and dial impulse detect.

Relaying drives output.

The scope of application is extensive.

Receiving gain is able to programme.

Its circuit as shown in Figure 5.

MH88612C is the core of subscriber line interface module, as seen from Figure 5 its needs+5V ,-5V ,-48V voltage, these voltages are provided by power module.

This chip also connects a ring flow-generator by relay, because ringing current generator cost very high (1W will 100 polylith money), therefore do not adopt ringing current generator, do not pass through ringing telephone stations, and in this module, use Music Clip and buzzer, when the needs ring, the buzzer jingle bell just can.Can save 80% cost like this.

(2), the circuit of local telephone (XO) interface

This module is equivalent to plain old telephone, has dialing, ring detection and speech transmissions function, and block diagram as shown in Figure 6.

Ring detecting circuit can use the MC145447 chip.Local line interface is in the on-hook attitude at ordinary times, and when occurring the ringing-current signaling on the telephone wire, ring detecting circuit detects this signal, the output high level, and indication has call.The control circuit module control relay is connected the speech transmissions interface chip, connects phone.During to outcall, relay is connected the speech transmissions interface chip, is equivalent to user's off-hook at needs, import dialling the number of 4bit then, export corresponding Dual Tone Multifrequency audio signal by the dtmf dialing device, serve telephone wire, carry out voice-frequency dialing by the speech transmissions interface chip.The dtmf dialing device has UM91531, TP5088 etc.

In a word, this module be exactly one by monolithic processor controlled automatic telephone.Because telephony is quite ripe, cost is low, so this module realizes being easier to.

(3), data control circuit and Ethernet interface module

This module is responsible for quantification, the coding of voice signal, and the compression of speech data, packing (weaving into the IP bag) also will provide control, the Man Machine Interface (as liquid crystal display output, switch control etc.) to each module and Ethernet interface is provided.The block diagram of this module is as shown in Figure 7:

The effect of multiway analog switch is to switch subscriber line interface and local line interface for this module among the figure.PCM CODEC is the PCM coder, has AD, DA translation function concurrently.This class chip has TLV320AIC22, TCM38C17, STAC9721 etc.

DSP and single-chip microcomputer are the cores of this module.Dsp operation speed very fast (100MHz) is used for compress speech, decompression and realizes data processing aspects such as IP agreement, packing data; The single-chip microcomputer speed of service is slower, is used at a slow speed external control and liquid-crystal display section.Communicate by letter co-ordination by IO between DSP and single-chip microcomputer.(note: in order further to save cost, can consider DSP is saved, voice do not compress, and directly transmit with PCM.Because the Ethernet interface bandwidth can meet the demands).

The Ethernet interface chip is exactly the acp chip on our the present network interface card that uses, and is used to provide network interface.

SRAM provides more program running space as the exented memory of DSP to DSP.EEPROM is used for storing the DSP program, and some configuration datas.

Introduce the chip type selecting below.Through a large amount of screenings, we have adopted the model of DSP, single-chip microcomputer, Ethernet interface chip and LCD display:

■DSP

Select the TMS320C5402 of Texas Instruments for use.It is fixed-point dsp (DSP), and its internal price is more than 50 a yuan of RMB, and main feature is as follows:

Operation rate reaches 100MIPS;

Has advanced multiple bus architecture, three 16 bit data memory buss and a program storage bus;

40 ALUs (ALU) comprise 40 barrel shifters and two 40 bit accumulators;

One 17 * 17 multiplier and 40 special-purpose adders allow 16 bit strips/not signed multiplication;

Integrate the Viterbi accelerator, be used to improve the speed of Viterbi coding and decoding;

Monocycle normalization and index decoding;

8 background registers and a software stack allow to use the state-of-the-art fixed DSP C of industry CompilerTools;

Data/program addressing space 1M * 16bit, built-in 4K * 16bit Rom and 16K * 16bit RAM;

The HPI mouth that built-in waiting state generator able to programme, phase-locked loop (PLL) clock generator, two multichannel buffer serial ports, 8 parallel-by-bit are communicated by letter with ppu, 2 16 bit timing devices and 6 passage dma controllers;

Low-power consumption, working power have 3.3V and 1.8V (kernel), are particularly suitable for battery supply set.

144-Pin Plastic Low-Profile Quad Flatpack (LQFP) (PGE Suffix) encapsulation or 144-PinBall Grid Array (BGA) (GGU Suffix) encapsulation.

The ■ single-chip microcomputer

Select the AT89C51 of atmel corp for use.Its characteristics and brief introduction are taken passages as follows:

With MCS-51 ^TMThe product compatibility

But the internal system overprogram Flash memory of 4K byte

Operating frequency is 0Hz to 24MHz

3 grades of program storages lock

128 * 8 internal RAM

Article 32, programmable I/O circuit

2 16 bit clocks/counters

6 interrupt sources

Programmable serial type passage

Low-power consumption when unloaded

AT89C51 has 32 programmable I/Os, for externally control and exchanges data are provided convenience.It has 6 interrupt sources, can be used for interrupting waking up, for example off-hook detection signal or ring detection signal is received on the interrupt source, and DSP and single-chip microcomputer all are in sleep state to reduce power consumption during no signal, then wake DSP and single-chip microcomputer work up if any signal.

■ Ethernet interface chip

Select the RTL8019AS chip of REALTEK company for use.This chip is the chip that present most of popular 10M network interface cards are selected for use, and its main performance is as follows:

Be adapted to Ethernet II, IEEE802.3,10Base5,10Base2,10BaseT;

Support 8,16 bit data bus;

Full duplex, transmitting-receiving can reach the speed of 10Mbps simultaneously, has sleep pattern;

The SRAM of built-in 16KB is used for the transmitting-receiving buffering, reduces the rate request to primary processor;

Coaxial cable and twisted-pair feeder can be connected, and the medium that is connected can be detected automatically;

The PCB size is dwindled in the TQFP encapsulation of 100 pin.

Its brief introduction of work principle of RTL8019AS is as follows:

Primary processor (being DSP among the design) can be mapped to 16 registers on the I/O address by it and finish operation to RTL8019AS.By the difference of data link, the RTL8019AS inner passage can be divided into long-range DMA (remote DMA) passage and two parts of local DMA (local DMA) passage.Local DMA finishes the exchanges data of controller and netting twine, and the primary processor transceive data only needs long-range dma operation.When primary processor will be to online transmission data, earlier frame data are delivered to transmission buffer area among the RTL8019AS by long-range DMA passage, send then and transmit order.RTL8019AS finishes the transmission of this frame again after the transmission of having finished previous frame.The data that RTL8019AS receives by MAC comparison, CRC check after, deposit by FIFO and to receive buffering area, receive a full frame after, interrupting or the mode of register flag is notified primary processor, primary processor deals with again.

RTL8019AS datasheet.http is seen in the detailed description of this chip: //www.realtek.com.cn.

4) LCD display

Select the MDLS series LCD of the fluffy company far away of smart electricity for use, two style of writing words show that the English character collection is with backlight.This display is by Single-chip Controlling, the demonstration of the register controlled LCD by read-write display controller (LCM).Utilize the Man Machine Interface of LCD, the convenient control of the mode that can adopt menu to show as adapter.

What should be noted that when designing this module a bit is: because the highest permission incoming level of the IO of TMS320VC5402 is 3.6V, and Ethernet interface chip RTL8019AS and single chip computer AT 89C51 are operated in standard Transistor-Transistor Logic level 5V, if their IO directly links to each other with the IO of TMS320VC5402 then can cause damage to TMS320VC5402.Therefore, between them, need to add the one-level level translator.Through investigation, we adopt No. 163245 chips of 74 series to meet the requirements.It is two voltage bus transducers (16-Bit Dual Supply Bus Transceiver) of 16.The TC74LCX163245FT that Toshiba produces is exactly the transducer of a 5V of being specifically designed to, the trunk mixed circuit of 3.3V.Its phase shorter workweek is 7ns, therefore is applicable to the bus of 100MHz.

Because the IO of TMS320VC5402 output high level is about 3.3V, meets TTL electrical equipment logic high standard (＞2.5V gets final product),, only need to add this one-level at data/address bus so the address bus that DSP externally exports needn't power up the parallel operation of flatting turn.Also have input control interface such as interrupting input end also to need electricity will add the parallel operation of flatting turn at DSP.

5) power supply

By the introduction of top each module as can be known, transducer needs the multivoltage power supply.We wish that adapter only needs external power supply input, as the AC-DC transformer of AC220V-DC12V, in the conversion of the inner realization of adapter multivoltage, therefore need this module of power supply then.

Power module is input as the 12V direct current, need output-48V ,+5V ,-5V ,+3.3V ,+five kinds of voltages of 1.8V.Realize that dc voltage conversion has special chip, be called Switching Power Supply.

12V changes to-the voltage transformation chip of 48V is difficult to look for, do not find, at last we to have selected Beijing Yihongtai Technology Development Co., Ltd.'s model for use be the DC/DC modular power source of NR12D24/100, input DC12V, output ± 24V, 100mA.Press figure below wiring promptly exportable-48V:

The said firm provides the power supply product of the following DC/DC of 300W, AC/DC, ringing current generator, nearly thousand kinds of four series of isolated amplifier, but because this generic module power supply is more expensive and volume is big, so we do not use modular power source in all the other four kinds of voltage transformations, and adopt relevant chip.

The 12V-5V decompression transformation adopts 7805 chips, and the 5V--5V voltage reversal adopts ICL7660, and the 5V-1.8V decompression transformation adopts the TPS76918 chip, and the 5V-3.3V decompression transformation adopts the TPS76933 chip.

Virtual city call commentator has 5 kinds of mode of operations:

Configuration mode;

Common local telephone network Transfer Mode;

The direct calling pattern of point-to-point;

The virtual local telephone call model;

The local telephone network switch mode.

(1) configuration mode

Finish the configuration of system's relevant parameter, for example: the IP address of IP address, gateway address, reciprocity adapter and switch mode etc.

(2) common telephone call pattern

On this pattern, the user uses ordinary telephone set can only call out local local telephone network, and at this moment, A, B interface link to each other, and just are equivalent to a Daepori and take on the telephone.But to incoming call, the user can answer local local telephone network.And, also can answer virtual local telephone (long-range local telephone network).When if the ether interface C of city call commentator (hereinafter to be referred as adapter) has calling, adapter will be handled annexation according to substation current state (on-hook or off-hook attitude).Disconnect A, B and connect when on-hook, connecting interface A and interface C give switch with calling; When off-hook to the adapter loopback of calling out " user is busy " signaling.

(3) point-to-point direct calling pattern

This pattern can only be used for the calling of two reciprocity adapters, is connected on subscriber phone on the adapter, for example the user A calling party B among Fig. 1 by internet call the other side.Adopt particular number to call out this moment, as press the # key.

(4) call model of virtual local telephone

This mode adopts the Local Number to call out any phone of distant city by the Internet and long-range local exchange.For example: user A use local call (number 777776) wants to call out the phone (number is 62788888) in the distant city among Fig. 1, then user A only needs to adopt the local telephone network dial mode to dial 62788888 in this locality, then can connect phone 62788888 by adapter in the distant city and switch.Therefore just can realize virtual local telephone communication (both are not or not same city) between 777776 phones and 62788888, this cost of the phone call only need be paid local telephone expense and network expense.

(5) local telephone network switch mode

The switching of direct calling pattern and virtual local telephone call model can have been adopted artificial mandate and authorize dual mode automatically.

Under the artificial authorization, if local user's first requires long-range adapter to switch to the ordinary call pattern of virtual local telephone, then at first adopt direct calling mode call remote user B, come toggle switch, remote transducer is switched to the common local telephone network method of calling of long-range local telephone network by user B.

Automatically under the authorization, if local user A requires long-range adapter to switch to the ordinary call mode of long-range local telephone network, then

Local user A only needs to make remote transducer automatically switch to the method for calling of virtual local telephone to remote transducer input password.

Adopt authorization from security standpoint, prevent that adapter is stolen.

Specific implementation is as follows:

Describe each main modular hardware designs of adapter above in detail, introduce relevant software realization mode below.

(1) privately owned signaling

We are in exploitation during adapter, and proprietary protocol is adopted in the communication between two adapters.We have mainly defined following message and have finished signaling procedure:

Offhook message: the signaling procedure of finishing off-hook.

On-hook message: the signaling procedure of finishing on-hook.

User's message of hurrying: called adapter sends this message and informs that to call out the adapter callee busy.

Request virtual local telephone message related to calls: be used for remote dummy local telephone network call model.Local adapter sends this message request to long-range adapter and dials journey virtual local telephone called telephone.

Authorization message: be used for remote dummy local telephone network call model.The remote port adapter sends this message to the requesting party and informs that it dials the authorization of remote dummy local telephone network.

Dial message: be used for remote dummy local telephone network call model.Sending this message to long-range adapter controls it and dials to local telephone.

Jingle bell message: be used for direct calling and remote dummy local telephone network call model.To calling out this message of adapter loopback, the callee is just at jingle bell in indication when called adapter ring.

Code message: be used for remote dummy local telephone network call model.Send the password that the request of transmitting of this signaling is authorized to long-range adapter.

Called IP message is set: be used for the local telephone network switch mode, the user is by the IP of the called adapter of available this message remotely modifying adapter acquiescence after authorizing, so that receive the phone of switching on the road.

Point-to-point direct calling message: be used for the direct calling pattern.Realize the direct calling between two adapters.

(2) each mode of operation implementation method

The configuration feature of ■ configuration mode is realized

Single-chip Controlling analog switch connecting subscribers participating line interface module under this pattern, the user utilizes telephone set can be configured adapter as input equipment.Its key technology is that DTMF detects, the specific touch-tone signal that sends when promptly detecting the audio telephone button by DSP.Detect this signal and just can know the key that the user presses.Discernible button comprises 0～9, and *, # be totally 12 keys.The parameter that adapter need be provided with has: this machine IP address, gateway ip address, subnet mask, whether allow automatic mandate, the automatic IP address etc. of licencing key, long-range adapter.

The realization of incoming call under the ■ common telephone call pattern

Under this pattern, subscriber line interface module and subsets disconnect, and subscriber phone directly is connected with local telephone, but control module still monitors the calling of automatic network, connects the local line interface module simultaneously.This moment, subscriber phone and local line interface module were connected in parallel on the local telephone.If detected calling network, and local telephone does not have calling (promptly do not have ring stream signal, subscriber phone is not in ringing condition), then adapter ring, otherwise loopback " user is busy " signaling.In the time of the adapter ring subscriber phone is switched on the subscriber line interface module, control module also switches to the subscriber line interface module.Connection diagram as shown in Figure 9.

■ point-to-point direct calling pattern

Under this pattern, behind user's off-hook, adapter is waited for subscriber dialing (the IP address of called adapter), this moment, the user also can press the * function key, enter the menu of selecting to store number, adapter is gone up in LCD (LCD) and is shown called list, allows the user select.The local adapter of hypothesis (user A) will be directly called long-range adapter (user B) below, and its process is as follows:

After user A has imported the IP address of user B, control module " call signaling " call targets IP adapter B.Adapter B receives the state that detects subscriber phone after this signaling, if when being in the on-hook attitude with regard to ring and loopback " jingle bell signaling ", if when being in the off-hook attitude with regard to loopback " user hurry signaling ".Adapter A is according to phone playing RBT or the busy tone of the signaling of returning to user A.

If user B off-hook, adapter B sends " off-hook signaling " to A, starts voice reception, decompression thread Voice_Receive and compress speech, transmission thread Voice_Send simultaneously, connects the voice channel of party B-subscriber's phone.Adapter A stops playing RBT after receiving " off-hook signaling ", start Voice_Receive and Voice_Send thread, connect the voice channel of party A-subscriber's phone, the ip voice passage between user A, B has just been got through fully like this, just can realize the direct connection between two adapters.

■ virtual local telephone call model

Under this pattern, behind user's off-hook, adapter sends " request virtual local telephone message related to calls " to the long-range adapter of acquiescence, and long-range adapter is received after this signaling according to its state loopback " user hurry signaling " or " authorization signaling ".Call out adapter and play busy tone or authorize the indication sound to subscriber phone, simultaneously show state on LCD according to returning signaling.

If automatic authorization, the user need input password.The password of input sends to long-range adapter by " password signaling ", and long-range then adapter starts Voice_Receive and Voice_Send thread, the voice channel of call establishment subscriber phone.If password is correct, the control module of long-range adapter is connected the local telephone network interface module, and its subscriber phone and local telephone are disconnected, and its annexation is seen Figure 10.

The relay of long-range adapter control local telephone network interface module, the state that engages with ring detecting circuit when making local telephone by on-hook transfers the off hook state that engages with the speech transmissions interface to.This has been equivalent to simulate the off-hook process of Daepori energising phone.At this moment, subscriber exchange PBX just should be to local telephone Sending dialled number sound.The DSP of long-range adapter starts the Voice_Send thread simultaneously, so will mail to client with the form of packets of audio data from the dialing tone of PBX.DSP also will start the Voice_Receive thread, and this thread is monitored the packets of audio data from calling terminal, be responsible for these packets that decompress, and externally output to PCM decoding, analog-digital chip, finally be loaded on the local telephone by the speech transmissions interface.

Because the IP voice-grade channel of calling terminal adapter is set up, so the calling party can hear the dialing tone from PBX, thereby knows that long-range adapter and being connected of local telephone are intact, can begin to have dialled.

If password bad, long-range adapter is not done any response, and the calling party will can not hear trunk tone.

If long-range adapter is artificial authorization, then require the calling party by a specific key, as " 0 " numerical key, start authorized call.This calling is to make the calling party adapter send " call signaling " to long-range adapter, makes its ring.If long-range adaptor end has the people, receive calls, then the calling party user can ask long-range adapter user of service to be its mandate.If long-range adapter user of service allows calling party to dial off-net telephony, he can press a mandate key on the long-range adapter, long-range adapter just becomes annexation Figure 10 connected mode automatically, and the calling party just can connect the local telephone of long-range adaptor end.

Calling party user begins dialing, and its number is exactly the plain old telephone number.For example, suppose long-range adapter in the B city, just needn't dial area code when then the calling party user dials telephone number in the B city.The calling party adapter sends to long-range adapter with the number of being dialled with " dial signaling ", and abandons the pairing DTMF speech data frame of number.This handles by the DTMF_Recognize thread.DTMF_Recognize judges a frame speech data.In case be judged to dtmf signal, these frame data have just abandoned, do not recompress, send, in order to avoid cause long-range adapter to repeat to take place dtmf signal: because dtmf signal also is an audio signal simultaneously, if its packets of audio data also sends to long-range adapter, output will be loaded on the telephone line after decoding, and is equivalent to dial to PBX.Because network delay and voice buffering (Jitter Bufer) time-delay, the dial signaling bag will arrive first long-range adapter, the dtmf dialing device that it can control the local line interface module produces dtmf signal, every a period of time of after dtmf tone audio data bag also arrived, produce same dtmf signal again, if interval time is longer, telephone exchange will think to have dialled two numbers, makes the mistake.Why using the dtmf dialing device, is in order to generate the standard DTMF signal.

Because voice-grade channel is set up, after finishing, subscriber dialing (judges) by telephone office switch, will hear feedback signal sound:, hear ring-back tone if put through from phone end office (EO); If obstructed, hear busy tone.If the called phone off-hook, calling party just can be known from sound, and conversation just can begin; The called phone on-hook, calling party will be heard busy tone, also just knows end of conversation.If calling party user's on-hook, the calling terminal adapter detects this incident, sends " on-hook signaling " to long-range adapter, and after long-range adapter was received, the relay of control local line interface module disconnected the telephone wire loop, realizes the on-hook of long-range adapter.

Under this pattern, pass through in case authorize, calling party and long-range adapter are just set up a transparent talking path, and whole equivalence is a telephone set.

■ local telephone network switch mode

This pattern is that a kind of energy will be transferred to the mode of operation of the called adapter of acquiescence from the calling of local telephone, can realize the function of local telephone network roaming.Under this pattern, the control module of adapter links to each other with the local line interface module, and telephone set and local telephone disconnect, and annexation is just with shown in Figure 11.If the calling from local telephone is arranged, ring stream signal is promptly arranged, and after the ring detecting circuit of local line interface module detected, ring detected and just is output as, control module sends " ring signaling " to the called adapter of acquiescence, and called adapter is according to its state ring or loopback " user hurry signaling ".Adapter under the note Transfer Mode is adapter A below, and called adapter is adapter B.A waits for that B returns the off-hook signaling.Do not have response as B, A just waits for always that nobody connects to be equivalent to phone.

If user's off-hook of adapter B, with off-hook signaling form notice A, A starts Voice_Send and Voice_Receive thread to B this incident, then drives relay and connects telephone wire and speech transmissions interface, analog telephone off-hook.Arrive this, voice-grade channel is set up fully, and the roamer just can utilize adapter A and user B to talk.

Under the manner, the telephone set that adapter connect can not be answered the phone from local local telephone, because these phones all can be forwarded.But, all can answer from the calling of other adapter.Give an example below this mode implementation procedure is described.

For example user A family is in Beijing, the Guangzhou of going on business to.He is connected on adapter A on the telephone wire and netting twine of family, and is made as " local telephone network roam mode ".He is being with adapter B to arrive Guangzhou, connects adapter B and distributed IP for it in hotel room.By automatic mandate, he is made as " IP of the called adapter of acquiescence " of the adapter A of family the IP of adapter B, like this, every phone of getting to his family all can forward to the form of IP phone on the phone that adapter B connect, he just can answer the call as at home, thereby realizes the roaming of local telephone network.In addition, he also can utilize the function of adapter A " virtual local telephone function ", dials Beijing local telephone.

This shows that advantage of the present invention is as follows:

Utilize Internet technology and proposed a kind of brand-new Internet-based communication products in IP phone gateway technical foundation. This product is to utilize the internet to extend a certain local user's line. It not only has the cheap advantage of IP phone, and product cost low (hardware cost is below 500 yuan), powerful (can realize multiple conversation pattern), uses the advantage of simple (not needing other optional equipments on the basis of existing telephone system). Simultaneously can realize that a certain local telephone network is in global roaming.

Claims (1)

1. virtual city call commentator, it is characterized in that containing: Subscriber Line Interface Circuit (XS), local line interface circuit (XO), relay, dual tone multi-frequency dtmf dialer, power supply, multiway analog switch module, PCM codec PCM CODEC module, dsp processor module, Ethernet interface chip module and one-chip computer module, wherein:

The multiway analog switch module, be a data control circuit, be provided with the input of phonetic entry 1, the off-hook detection signal input part, the input of phonetic entry 2, ring detection signal input, the dialing control input end, the input that connects described PCM CODEC output signal (OUT), the input that connects single-chip microcomputer signal output (C_O), the output of voice output 1, the ring control signal output ends, the output of voice output 2, the dialing control output end, the output that connects PCM CODEC input signal (IN), the output that connects single-chip microcomputer input signal (C_I);

Described PCM CODEC module, be provided with the input that connects multiway analog switch output signal (IN), the input that connects DSP module output signal (PCM_OUT), the output of connection DSP module input signal (PCM_IN), the output of connection multiway analog switch input signal (OUT);

The dsp processor module is that a digital signal processor DSP adopts chip TMS320C5402, be provided with the output that connects PCM CODEC module input signal (PCM_OUT), the input that connects PCM CODEC module output signal (PCM_IN) also is connected with one-chip computer module with the Ethernet interface chip module respectively by the I/O passage;

The Ethernet interface chip module is a RTL8019AS, connects Ethernet by the RJ45 interface, connects the DSP module by the I/O passage;

One-chip computer module is that a single-chip microcomputer that is connected with LCD display adopts the AT89C51 chip, connect the DSP module, be provided with the input that connects multiway analog switch module output signal (C_I), the output that connects multiway analog switch module input signal (C_O), by the I/O passage by 4 dialed numbers of output channel output;

Subscriber Line Interface Circuit (XS) is chip MH88612C, is used for directly connecting the Tip pin, Ring pin of subsets and the I/O end of described control circuit interconnection;

Local line interface circuit (XO), contain the speech transmissions interface chip, one end links to each other with the Ring pin of local telephone, this speech transmissions interface chip also has the I/O (Tx, Rx) of voice, ring detecting circuit one end links to each other with local telephone Tip pin through relay contact C3 when user's on-hook, this end does not link to each other with the B2 point of speech transmissions interface chip through another contact of relay C2 when user's off-hook is called out again, and it is A2 that the ring of this ring detecting circuit detects output; The coil of relay is controlled by described data control circuit through a C1; The dual tone multi-frequency dtmf dialer, the signal input part (B3) of output (D1) and described speech transmissions interface chip links to each other, and input has two, is respectively input of dialling the number (D2) and dialing signal input end (D3);

Power supply is given described Subscriber Line Interface Circuit (XS), local line interface circuit (XO), data control circuit and Ethernet interface power supply;

Described power supply is made up of with chip IC L7660,5V-1.8V decompression transformation chip TPS76918,5-3.3V decompression transformation chip TPS76933 the AC-DC transformer of the AC220V-DC12V that links to each other with external circuits, the decompression transformation chip 7805 that links to each other with this transformer output, 5V--5V voltage reversal;

The virtual local telephone call model of described virtual city call commentator, its job step is as follows successively:

Behind step (1) user's off-hook, the adapter of calling party sends the signaling of " the request virtual local telephone is called out " to the callee's who has given tacit consent to adapter;

This callee's of step (2) adapter is received after the signaling according to the oneself state loopback of returning " user hurry signaling " or " authorization signaling ";

The adapter of step (3) calling party is put busy tone or is authorized the indication sound to the subscriber phone end according to returning signaling, shows on LCD simultaneously;

Step (4) realizes the virtual local telephone calling by following different step respectively according to the classification of authorization;

If authorization, then realization according to the following steps automatically:

Step (4.1) user inputs password;

The password of step (4.2) input sends to callee's virtual city call commentator through the Internet by " password signaling ";

Step (4.3) callee's adapter then starts Voice-Receive and Voice-send thread, call establishment user's voice passage;

Step (4.4) is if password is correct, and the control circuit of callee's adapter is just connected the local telephone network interface circuit, and subscriber phone and local telephone are disconnected, and enters virtual local telephone switching state;

Step (4.5) callee's adapter makes local telephone transfer the off hook state that engages with the speech transmissions interface to by relay;

Step (4.6) subscriber exchange is to local telephone Sending dialled number sound, and simultaneously, the DSP of callee's adapter starts Voice Send thread, so just mail to client with the form of packets of audio data from the dialing tone of subscriber exchange;

Step (4.7) is as if password bad, and then callee's adapter does not have response;

If artificial authorization then realizes according to the following steps:

Step (4.1) user starts authorized call by particular key, and the adapter transmission " call signaling " to the callee makes its ring;

Step (4.2) callee's adapter user of service just presses a mandate key on the adapter, comes the local telephone of the adaptor end of authorized call user called number with this.

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