Timing Advance Command Extension for Wireless Range

The patent changes the timing advance command parameters by transmitting multiple timing advance commands (first and second commands) with different timing advance values. This allows the mobile unit to combine these commands to achieve a cumulative timing advance that extends the effective coverage range beyond what a single command could provide, without proportionally increasing the guard time or cyclic prefix duration.

The patent segments the timing advance adjustment into multiple discrete commands transmitted at different times. Instead of requiring a single complex timing advance command to cover the entire extended range, the system divides the timing advance adjustment into multiple smaller steps (first timing advance command, second timing advance command), which the mobile unit combines to achieve the total required timing advance for extended range synchronization.

The patent employs periodic transmission of timing advance commands, where the base station transmits additional timing advance commands at specific intervals or under specific conditions. This periodic action allows the system to extend coverage to mobile units at the cell edge while maintaining efficient signaling for mobile units within the normal coverage area, thereby reducing overall signaling overhead compared to continuously transmitting multiple commands to all mobile units.