Synchronization signal block transmission

An apparatus, comprising:

• at least one processor;
• and
• at least one memory including computer program code,
• wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to:
• initiate receiving synchronization signal blocks in positions,
• wherein the positions include first positions associated with an initial transmission attempt of the synchronization signal blocks, and include second positions, respectively associated with the first positions, reserved for retransmission of the one or more synchronization signal blocks that failed to transmit in the first positions,
• wherein the first positions comprise multiple subsets of the first positions,
• wherein the second positions comprise multiple subsets of the second positions respectively associated with different subsets of the multiple subsets of the first positions,
• wherein the subsets of the second positions occur between the multiple subsets of the first positions,
• wherein the first positions and the second positions are located in a single discovery burst transmission window;
• monitor a second subset of the subsets of the second positions for the synchronization signal blocks based on failing to detect the synchronization signal blocks in a respective first subset of the subsets of the first positions, wherein the second subset of the subsets of the second positions to be monitored is respectively associated with the first subset of the subsets of the first positions;
• determine whether the synchronization signal blocks were received in the first positions or the second positions based on an indication in the synchronization signal blocks, the indication identifying a first synchronization signal block of the synchronization signal blocks as being transmitted in a first retransmission position in the second subset of the subsets of the second positions;
• determine a synchronization signal block index (SSB index) based on determining that the synchronization signal blocks were received in the second positions, the SSB index is determined based on a physical broadcast channel demodulation reference signal and one or more bits associated with a physical broadcast channel physical layer;
• and
• determine a slot timing based on determining that the synchronization signal blocks were received in the second positions, the slot timing is determined based on a common subcarrier spacing field of a master information block.