The grouping based on SYS6K voice processing module Design (1)

0 introduction

Current telecom services to voice and broadband data, use two network construction phase superimposed.

SYS6K system precisely has voice, data, NGN triple play of technology trends, full integration of the narrow-band circuit technology, NGN grouping technology and broadband technologies, provides an object-oriented NGN and PSTN, integrated services access platform solution. SYS6K integrated access media gateway, consistent with industry standard People's Republic of China telecommunication YD/T1243.3-2002. This article describes the design of packet voice processing module is the integrated access media gateway completes the PCM and IP data conversion and some media protocol handling of function modules.

1SYS6K system design requirements

SYS6K is to offer comprehensive service access bulk access media gateways, simulation provided user access, ADSL access, VDSL access, SHDSL access functions.

For the analog user access, access to both E1 interface access traditional PSTN switches also provide 10M/100M/1000M Ethernet access IP network.

Hosted in the traditional voice over IP is a trend that now all major carriers are also launched NGN projects.

So not only can meet the needs of current PSTN business, and achieve a smooth transition to the NGN products is operators expect. The programme provides the above SYS6K two main ways of compatibility is based on the Bureau's business requirements. Packet voice processing module is one of the main control board, the matching function module or stepped up selected according to the data or go to El VoIP, its major functions done voice processing, provide analog voice into IP packets between the conversion. Early media gateway development, complete the required signal processing, signalling, packaging, and control functions, as well as send compressed or uncompressed VolP packet (voice-over-packet).

AMU is IONEAX6000 integrated access media gateway for the main control board, is the realization of media gateway functionality of main parts, narrow-band speech switching and broadband data exchange between the two parts.

Narrowband voice Exchange by CPU control unit, E1 interface unit, HW time slot switching units, security logical unit, VoIP DSP cells and modules. Broadband data exchange by CPU control unit, GALILEO layer 2 switching set of tablets and-Gigabit optical interfaces. Narrowband voice exchange part of CPU processor complete MGCP, narrowband business management, continuous control, external serial port management and main and control functions. E1 interface unit complete 2MPCM stream to convert, and 8MHW from PCM in narrowband reference clock work. HW time slot switching unit is composed by two IDT72V70840, can provide PSTN telephone voice exchange and DDN data exchange, both business in two independent processing in the mesh. Security logical unit for narrow-band clock handling, on VoIP module and CPU to classify the current limit of data as well as the MAC address and IP address. VoIP module complete HW signal and IP conversion between data flow, realization of the traditional PSTN voice signal transmission over the Internet, you can make IONEAX6000 from traditional access device smooth transition to the next NGN equipment. DSP unit complete standard signal sound broadcasting, receiving number detection.

2 analysis of packet voice processing modules

VoIP functionality basically divided into two according to the majority, one voice codec is a compression and decompression, the second is to IP packets and sending and receiving of voice information.

The packet voice processing module (PVM) function that implements the PCM and IP data conversion and media control and processing to buckle by form in the system as a function of the main control board. In the entire system from the main control board control business, such as call establishment, management and shutdown, and so on, the main Control Board to manage the configuration of this module, as the buckle in the system is controlled at all times. And each time you reset all need master plate configuration load configuration, so this module fault handling, reset or not is determined by the main control board, and not by buckle to decide whether to reset. It and the relationship between the master control panel is always controlled, its signal to the profile of the main control board broadband and narrowband segment.

3 integrated access media gateway SYS6K programme

SYS6K is box-integrated structure, sets the analog user access, ADSL access, VDSL access, SHDSL access functions integrated access media gateway, by power plate PTU, master plate AMU, business panels ALU, ADU

, VDU, IVD, SDU, etc. Packet voice processing module PVM is the main control board a functional AMU can matching buckle.

Broadband data portion of the CPU system uses Motorola's 8245CPU system, provides a 32-bit PCI interface and LOCALBUS connectors.

PCI bus can support up to 5 devices, 8245 through the PCI bus can be configured to GALILEO48303, and then through the GALILEO company defined the GUNK bus business network I, uplink Gigabit optical ports for routing module for data exchange. General diagram of AMU veneer like Figure 1.

3.1 narrowband voice exchange part

Narrowband voice exchange part of complete access to PSTNEl signal, E1 and PCM signal between the conversion, exchange between PCM slot, PCM voice and IP conversion between data flow, security logic functions.

The main signal flow is E1 chip receive PSTN network sent to E1 signal, extract 2M clock signal as the benchmark for narrow-band system, and thus produce the clock each chip required clock and frame synchronization signal. At the same time, the PSTN network sent to E1 signal through E1 chip, the encoding type from HDB3 converted to NRz, then fed into the mesh for PCM slot Exchange, give the user Board, or to PVM buckle for processing. Because the system itself also provides user access to PSTN network simulation, in TDM interface portion of the main control board AMU and narrowband plates ALU has completed the analog signal to digital signal conversion. On voice services, there are two ways of processing, the system of E1 interface access PSTN switch or other relay equipment, or by grouping voice processing module in IP packet. System design into the PVM is already a PCM signal of the Highway.

3.2 broadband data processing part

Broadband data exchange section to complete the various access methods for base configuration, Ethernet switching and Ethernet management functions.

Broadband part structure diagram shown in Figure 2.

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