3Com MSR 30, MSR 50 manual Pri-set, Example # Adopt µ-law companding for signal quantization

2660 CHAPTER 175: E1 AND T1 CONFIGURATION COMMANDS

Companding laws are adopted to quantize signals unevenly for the purpose of reducing noise and improving signal-to-noise ratio. Underpinning this approach are the statistics about voice signals, which indicate that lower power signals are more likely present than high power signals.

According to CCITT, when devices in two countries use different companding schemes to communicate, the side using µ-law is responsible for converting signals to A-law.

n By default, the companding law for VE1 interfaces is A-law, while that for VT1 interfaces is µ-law.

Example # Adopt µ-law companding for signal quantization.

<Sysname> system-view [Sysname] voice-setup [Sysname-voice] subscirber-line1/0:0 [Sysname-voice-line1/0:0] pcm u-law

pri-set

Syntax pri-set [ timeslot-list range ]

undo pri-set

View E1/T1 interface view

Parameter range: Specifies timeslots to be bound. Timeslots are numbered 1 through 31 on an E1 interface and 1 to 24 on a T1 interface. You may specify a single timeslot by specifying a number, a range of timeslots by specifying a range in the form of number1-number2, or several discrete timeslots by specifying number1, number2-number3. When the range argument is not specified, only TS15 is bound.

Description Use the pri-setcommand to bind timeslots on an E1 or T1 interface into a PRI set.

Use the undo pri-setcommand to remove the timeslot binding.

By default, no PRI set is created.

When creating a PRI set on a CE1/PRI interface, note the following:

■TS0 is used for frame synchronization control (FSC), TS16 as a D channel for signaling transmission, and other timeslots as B channels for data transmission. You may bind the timeslots except for timeslot 0 into a PRI set (as the D channel, timeslot 16 is automatically bundled). This PRI set is logically equivalent to an ISDN PRI interface in the form of 30B + D. If no timeslot is specified, all timeslots except for TS0 are bound into an interface similar to an ISDN PRI interface in the form of 30B+D.

■For the created PRI set, the system automatically creates a serial interface named serial number:15.