Devices, systems and methods for accessing random access resource units of a wireless channel

A device, comprising:

• communication circuits configured to
• receive wireless trigger communications that identify resource units available for random access (RA RUs), each RA RU being a portion of a transmission channel of a wireless system;
• according to a contention procedure, selecting or not selecting one available RA RU as a transmission RA RU;
• in response to not selecting a transmission RA RU, monitoring for response communications that follow the trigger communications,
• determining remaining unselected RA RUs from the response communications, the unselected RA RUs being any RA RUs that remain after other wireless devices have selected RA RUs in response to the trigger communication,
• designating one RA RU from the remaining unselected RA RUs as an alternate RA RU;
• and
• transmitting uplink data on the alternate RA RU.

A system, comprising:

• a wireless device that includes,
• communication circuits configured to
• detect a wireless trigger communication that identifies resource units available for random access (RA RUs), each RA RU being a portion of a transmission channel of a wireless system;
• according to a contention procedure, selecting or not selecting one available RA RU as a transmission RA RU;
• in response to not selecting a transmission RA RU, identifying at least one unselected RA RUs from responses following the trigger communication, the unselected RA RUs being RA RUs that remains after other wireless devices have selected RA RUs in response to the trigger communication;
• and
• an antenna system configured to transmit uplink data on the unselected RA RU.