PBCH repetition

[dsilhavy]

Description

Repetition of PBCH

Background & Important terms

PBCH = Physical broadcast channel ,carries BCH, downlink direction

A base station can transmit a master information block (MIB), which contains a few important parameters that the mobile needs to acquire a cell, and is delivered on the broadcast control channel (BCCH), broadcast channel (BCH) and physical broadcast channel (PBCH)

Implementation steps & recommendations

tbd

Related specifications

• ETSI TS 103 720

[johannmika]

@jsroldan @dsilhavy I have added a sample file with Rel16 CAS including PBCH repetition in the sample-file section of the wiki.

[dsilhavy]

From @kuehnhammer slides:

Description

• Defined for MBMS-dedicated cells with at least 3Mhz bandwidth (not for 6 PRB / 1.4 MHz)
• PBCH REs from slot 1 symbols 1-3 are rotated and repeated in the three free symbols
• 5MHz / 25 PRB and higher: every CAS. 3 MHz: every second CAS (nf % 8 == 4).
• Reduces resource allocation for PDSCH

Implementation

• Configuration: modem -> phy -> bch_repetition_r16: true;
• Current implementation: PDSCH RA adapted. Repeated PDSCH symbols are not used.
• Improvements: Extend PDSCH CE to cover first slot, derotate and use repeated symbols