a system and method for adding a burst of a single - input multiple - output mode or collaborative spatial multiplexing mode to a frame in a spatial multiplexing system . a base station is configured to add a burst of a single - input multiple - output mode to a frame in a spatial multiplexing system . the system and method includes backing up a pilot pattern and a number of slots allocated for connections with terminals ; releasing slots allocated for a burst ; resetting a pilot pattern of a collaborative spatial multiplexing mode burst of the terminals : and recalculating the number of remaining slots ; comparing the number of slots that can be additionally allocated to the single - input multiple - output mode with the number of slots released in the releasing step ; and determining a transmission format .