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What is bits clock?

2020-03-01
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Bits is the abbreviation for building integrated timing supply equipment, and provides external clock for communication equipment. This article briefly introduces what is the bits clock and its functional characteristics.

The Bits clock equipment needs to provide synchronous state information. The main frequency synchronization signals of all kinds of transmission devices in China include: E1 signals (2048kbits/s) and 2048kHz frequency signals, and of course, T1 signals. But the most commonly used signals are E1 signals.

The bits channel of SDH can be understood as a channel for transmitting E1 signals on the ground link of the frequency synchronization network, and the SSM signal is transmitted in the E1 signal.

The SSM channel is a specific data communication channel for setting certain information. The main function of SSM is to transmit the quality level of the timing signal in the synchronous system. The SDH network and the node clock in the network get the upper clock information by interpreting it, and track, switch or transfer the clock to the node. At the same time, we need to transmit the resolved time information to the downstream.

To improve the quality of synchronous network signal and reduce cumulative error, clock devices usually mark all levels of synchronous source signals by SSM information.

Bits clock can be widely used in SDH network, SONET synchronous optical network, mobile communication network, accounting and operation and maintenance system. It supports the synchronization of mobile network time and frequency, provides frequency synchronization for fixed network devices, and has the characteristics of flexible configuration, complete functions and high performance price ratio, so as to meet the needs of time and frequency synchronization under different scenarios.

BITS device input and output levels are inconsistent, for example, two clock, input is a class of clock signal, output is two clock signal. The first class clock is the permanent clock and LPR. If you want to provide the two level clock signal, you need a two level clock node to accept the signal of the LPR level clock.
The level of the clock signal follows the level of the clock. The clock signal tracking by SDH is achieved through the STM-N bit stream extraction, which is equivalent to forming a clock bus, so the output clock signal level remains unchanged.

The SYN4124 BITS clock provides reliable synchronization for network operators. This device supports the synchronization of mobile network time and frequency, is the key node of synchronous network, and provides external clock for communication equipment. Support alarm (including alarm number, signal to noise ratio, location information, hardware failure, etc.) and alarm indication.

The BITS clock outputs nanosecond PTP/1588V2 and 1PPS+TOD high precision time synchronization signals, and at the same time provides 10 frequency synchronization signals with frequency accuracy of 10E-12 level. The types of frequency signals are complete, such as E1, 2048kHz, 1MHz, 5MHz, 10MHz, etc. The accuracy of time signal is better than 100ns.

The device supports SSM function for E1 interface, supports complex frame structure, satisfies the requirements of 6.4 articles in GB/T 7611 - 2001, supports configuration of bits with SSM information (Sa4, Sa5, Sa6, Sa7, Sa8), SSM function satisfies the requirements of 6.4 in 7611 7611 2001, and supports the function of correctly identifying, processing and forwarding SSM information.

The copyright of this article belongs to Xi'an in all respects, respecting originality, strictly prohibit manuscript, unauthorized, no reprint, copyright, infringement must be investigated!

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