BITS are the key nodes of synchronous network. It gets synchronized signals by tracking satellites or from cesium oscillator or from benchmark signals of higher-level time/frequency equipment, takes a series of process like selecting, filtering, tracking and maintaining, and then outputs stable and high-precision time/clock signals for downstream service devices such as GSM, WCDMA, CDMA, TD-SCDMA, LTE, SDH, Accounting system, BOSS and NMS. Therefore, the performance of BITS has great impact in the normal and stable operation of operators’ service. How to measure and evaluate the synchronization performance of BITS efficiently and accurately will be an important task that the equipment manufacturers and operators have to face.
The clock synchronization performance measurements of BITS mainly includes frequency accuracy, wander generation, jitter generation, pull-in/hold-in range, wander tolerance, noise transfer characteristics, jitter tolerance, phase transient, phase discontinuity, etc.
The time synchronization performance measurements of BITS mainly include absolute time accuracy, relative time accuracy, time stability, time-keeping accuracy, time source and switching performance when equipment has redundancy protection, frequency synchronization performance of internal clock, etc.
We can provide an integrated test solution for synchronous performance of BITS.
Fig 1 Frequency Measurement in BITS
Fig 2 Time Measurement in BITS