Multicast over wireless network with the assistance of power-efficient peer group discovery

A method of wireless communication of a receiver user equipment (UE), comprising:

• determining, at the receiver UE, to receive a multicast transmission for a multicast group having a multicast group identifier;
• wirelessly communicating, from the receiver UE, an expression, indicating an intention to receive the multicast transmission, with a sender UE in the multicast group at a time when the receiver UE is awake and before receiving the multicast transmission from the sender UE, the expression based at least in part on the multicast group identifier, an identifier associated with the receiver UE, and a discriminator that distinguishes the receiver UE from different receiver UEs, wherein the wirelessly communicating the expression comprises:
• determining, prior to communicating the expression, whether the sender UE is concurrently awake with the receiver UE to communicate the expression;
• and
• receiving an indication that the sender UE is ready to transmit the multicast transmission;
• and
• switching to a non-idle state and receiving the multicast transmission from the sender UE in response to receiving the indication from the sender UE.

An apparatus for wireless communication at a sender UE comprising:

• means for determining, at the sender UE, to send a multicast transmission for a multicast group having, a multicast group identifier;
• means for wirelessly communicating, from the sender UE, an expression, indicating an intention to initiate the multicast transmission, with at least one receiver UE in the multicast group at a time when the at least one receiver UE is awake and before sending the multicast transmission to the at least one receiver UE, the expression based at least in part on the multicast group identifier, an identifier associated with the sender UE, and a discriminator that distinguishes the sender UE from different sender UEs, wherein the means for wirelessly communicating the expression is configured to:
• determine, prior to communicating the expression, whether the at least one receiver UE is concurrently awake with the sender UE to communicate the expression;
• and
• receive an indication that the at least one receiver UE is ready to receive the multicast transmission;
• and
• means for switching to a non-idle state and sending the multicast transmission to the at least one receiver UE in response to receiving the indication from the at least one receiver UE.

An apparatus for wireless communication at a receiver user equipment (UE), comprising:

• means for determining, at the receiver UE, to receive a multicast transmission for a multicast group having a multicast group identifier;
• means for wirelessly communicating, from the receiver UE, an expression, indicating an intention to receive the multicast transmission, with a sender UE in the multicast group at a time when the receiver UE is awake and before receiving, the multicast transmission from the sender UE, the expression based at least in part on the multicast group identifier, an identifier associated with the receiver UE, and a discriminator that distinguishes the receiver UE from different receiver UEs, wherein the means for wirelessly communicating the expression is configured to:
• determine, prior to communicating the expression, whether the sender UE is concurrently awake with the receiver UE to communicate the expression;
• and
• receive an indication that the sender UE is ready to transmit the multicast transmission;
• and
• means for switching to a non-idle state and receiving the multicast transmission from the sender UE in response to receiving the indication from the sender UE.

An apparatus for wireless communication at a sender user equipment (UE), comprising:

• a memory;
• and
• at least one processor coupled to the memory and configured to:
• determine to send a multicast transmission for a multicast group having a multicast group identifier,
• wirelessly communicate an expression, indicating an intention to initiate the multicast transmission, with at least one receiver UE in the multicast group at a time when the at least one receiver UE is awake and before sending the multicast transmission to the at least one receiver UE, the expression based at least in part on the multicast group identifier, an identifier associated with the sender UE, and a discriminator that distinguishes the sender UE from different sender UEs, wherein the at least one processor is configured to wirelessly communicate the expression by:
• determining, prior to communicating the expression, whether the at least one receiver UE is concurrently awake with the sender UE to communicate the expression;
• and
• receiving an indication that the at least one receiver UE is ready to receive the multicast transmission;
• and
• switch to a non-idle state and send the multicast transmission to the at least one receiver UE in response to receiving the indication from the at least one receiver UE.

An apparatus for wireless communication at a receiver user equipment (UE), comprising:

• a memory;
• and
• at east one processor coupled to the memory and configured to:
• determine to receive a multicast transmission for a multicast group having a multicast group identifier,
• wirelessly communicate an expression, indicating an intention to receive the multicast transmission, with a sender UE in the multicast group at a time when the receiver UE is awake and before receiving the multicast transmission from the sender UE, the expression based at least in part on the multicast group identifier, an identifier associated with the receiver UE, and a discriminator that distinguishes the receiver UE from different receiver UEs, wherein the at least one processor is configured to wirelessly communicate the expression by:
• determining, prior to communicating the expression, whether the sender UE is concurrently awake with the receiver UE to communicate the expression;
• and
• receiving an indication that the sender UE is ready to transmit the multicast transmission;
• and
• switch to a non-idle state and receive the multicast transmission from the sender UE in response to receiving the indication from the sender UE.

A non-transitory computer-readable medium storing computer executable code for a sender UE, comprising code to:

• determine to send a multicast transmission for a multicast group having a multicast group identifier;
• wirelessly communicate an expression, indicating an intention to initiate the multicast transmission, with at east one receiver user equipment (UE) tithe multicast group at a time when the receiver UE is awake and before sending the multicast transmission to the at least one receiver UE, the expression based at least in part on the multicast group identifier, an identifier associated with the sender UE, and a discriminator that distinguishes the sender UE from different sender UEs, wherein the code to wirelessly communicate the expression is configured to:
• determine, prior to communicating the expression, whether the at least one receiver UE is concurrently awake with a sender UE to communicate the expression;
• and
• receive an indication that the at least one receiver UE is ready to receive the multicast transmission;
• and
• switch to a non-idle state and send the multicast transmission to the at least one receiver UE in response to receiving the indication from the et least one receiver UE.

A non-transitory computer-readable medium storing computer executable code for a receiver UE, comprising code to:

• determine to receive a multicast transmission for a multicast group having a multicast group identifier;
• wirelessly communicate an expression, indicating an intention to receive the multicast transmission, with a sender user equipment (UE) in the multicast group at a time when the receiver UE is awake and before receiving the multicast transmission from the sender UE, the expression based at least in part on the multicast group identifier, an identifier associated with the receiver UE, and a discriminator that distinguishes the sender UE from different receives UEs, wherein the code to wirelessly communicate the expression is configured to:
• determine, prior to communicating the expression, whether the sender UE is concurrently awake with the receiver UE to communicate the expression;
• and
• receive an indication that the sender UE is ready to transmit the multicast transmission;
• and
• switch to a non-idle state and receive the multicast transmission from the sender UE in response to receiving the indication from the sender UE.