Methods and apparatuses for radio communication

An apparatus comprising at least one processor, at least one memory including computer program code, and at least one communication module, the at least one memory and computer program code configured, with the at least one processor, and the at least one communication module, to cause the fast apparatus at least to:

• decide, based on at least one first parameter characterizing a signal power associated with at least one received downlink reference signal and based on at least one second parameter characterizing a signal power associated with at least one received sidelink reference signal, whether to transmit at least one sidelink synchronization signal;
• and
• transmit the at least one sidelink synchronization signal if the decision indicates that the at least one sidelink synchronization signal is to be transmitted.

An apparatus comprising at least one processor, at least one memory including computer program code, and at least one communication module, the at least one memory and computer program code configured, with the at least one processor, and the at least one communication module, to cause the first apparatus at least to:

• transmit at least one control information comprising at least one indicator, that causes a receiving apparatus, to decide, based on at least one fast parameter characterizing a signal power associated with at least one received downlink reference signal and based on at least one second parameter characterizing a signal power associated with at least one received sidelink reference signal, whether to transmit at least one sidelink synchronization signal.

A method comprising:

• deciding, based on at least one fast parameter characterizing a signal power associated with at least one received downlink reference signal and based on at least one second parameter characterizing a signal power associated with at least one received sidelink reference signal, whether to transmit at least one sidelink synchronization signal;
• and
• transmitting the at least one sidelink synchronization signal if the decision indicates that the at least one sidelink synchronization signal is to be transmitted.