The synchronization method adopted by China Power s outdoor LTE base stations

4 FAQs about The synchronization method adopted by China Power s outdoor LTE base stations

Which synchronization source should be selected?

In terms of the network listening synchronization source selection, the best accurate synchronization source to GNSS should be selected. If the Home base station obtains synchronization without using network listening, the small cell requirement applies. The requirement is 3.475 μs but in many scenarios a 3 μs sync requirement can be adopted.

Can a base station use a UTRAN synchronisation reference?

The Base Station shall use the same frequency source for both RF frequency Generation and the chip clock . The synchronisation reference extracted from the Iu may be used as UTRAN synchronisation reference. In principle (and in any case during loss of traceability from PRC), lower accuracy is sufficient (e.g. 16 ppb, as per Stratum 2).

How to synchronize downlink frames between base stations?

The downlink frames transmitted by the serving base station and the Neighbour base station shall be synchronized to a level of at least 1/8 cyclic prefix length (which is equal to 1.428 μs). 3 μs for small cell (< 500m radius). For large cell (> 500 m radius), 1.33 + Tpropagation ms time difference between base stations,

Which synchronisation reference should be used as UTRAN synchronization reference?

The synchronisation reference extracted from the Iu may be used as UTRAN synchronisation reference. In principle (and in any case during loss of traceability from PRC), lower accuracy is sufficient (e.g. 16 ppb, as per Stratum 2). Common SFN (System Frame Number) initialisation time shall be provided for all eNBs.