Methods and systems for patching direct-mode talkgroups among dual-watch mobile radios

A mobile radio that is a member of a first talkgroup associated with a first radio channel, the mobile radio comprising:

• a wireless-communication interface that includes first and second receivers;
• a processor;
• and
• data storage containing instructions executable by the processor for causing the mobile radio to carry out a set of functions that includes:
• residing the first receiver on the first radio channel;
• detecting either a first patch event or a second patch event, wherein the first patch event is receipt of a patch-initiation instruction for a first-channel patched-talkgroup session, wherein the second patch event is receipt of a patch invitation on the first radio channel from a second mobile radio that is a member of a second talkgroup associated with a second radio channel, the received patch invitation specifying the second radio channel for a second-channel patched-talkgroup session;
• responsive to detecting the first patch event, carrying out a set of patch-initiation functions that includes transmitting, via the wireless-communication interface, a patch invitation on each radio channel in a set of radio channels that are respectively associated with talkgroups in a set of talkgroups that includes the first talkgroup and at least one other talkgroup, each transmitted patch invitation specifying the first radio channel for the first-channel patched-talkgroup session;
• and
• responsive to detecting the second patch event, carrying out a set of patch-joining functions that includes residing the second receiver on the second radio channel.