Two-stage discovery in sidelink

A method for wireless sidelink communication between a first sidelink device and a second sidelink device, comprising:

• at a second sidelink device:
• receiving a sidelink discovery probing message from the first sidelink device, the sidelink discovery probing message identifying the first sidelink device;
• transmitting a probing response to the first sidelink device responsive to receiving the sidelink discovery probing message;
• and
• monitoring for a sidelink discovery message from the first sidelink device.

An apparatus for wireless communication at a first sidelink device, comprising:

• means for transmitting a sidelink discovery probing message comprising at least a first identifier of the first sidelink device;
• means for monitoring for a probing response from a second sidelink device;
• means for transmitting a sidelink discovery message if the first sidelink device receives the probing response from the second sidelink device;
• and
• means for skipping transmitting the sidelink discovery message if the first sidelink device does not receive the probing response from the second sidelink device.

A first sidelink device for wireless communication between the first sidelink device and a second sidelink device, comprising:

• means for receiving a sidelink discovery probing message from the first sidelink device, the sidelink discovery probing message identifying the first sidelink device;
• means for transmitting a probing response to the first sidelink device responsive to receiving the sidelink discovery probing message;
• and
• means for monitoring for a sidelink discovery message from the first sidelink device.