4G/LTE - LTE NB

NSSS (Narrowband Secondary Synchronization Signal)

Unlike other physical channel and signal, the characteristics of SSS (LTE) and NSSS(LTE-NB) differs widely. As compared below, SSS is based on m-sequence and NPSS is based on Zadoff chu sequence.

Another big difference between SSS and NSSS is Resource Element mapping and transmission pattern. As illustrated below, NSSS fills out 11 OFDM symbols from the end of a subframe (subframe 9). It is transmitted at subframe 9 of every two radio frames.