Patent ID: 6393064
Filing Date: 2002-05-21
Classification: H04L

Abstract:
A method of communication between a master device and a plurality of slave devices, wherein: (a) transmission from said master device to said slave devices use a downward transmission frame and transmission from said slave devices to said master device use an upward transmission frame, (b) at least one of the upward and downward transmission frames has a plurality of time slots, and (c) a first modulation method and a second modulation method are used to modulate said transmission between said master device and said slave devices, the method comprising:I. in a link setup phase: (a). transmitting information, specifying a communication time slot to be used in a communication phase, using one time slot each of said upward and downward transmission frames, and transmitting said information specifying a time slot to be used modulated by the first modulation method; (b). transmitting information between said master and said slave(s) specifying a modulation method to be used in a communication phase; wherein, if high speed communication is to be performed, the information specifying a modulation method to be used is the second modulation method, and if high speed communication is not to be performed, the information specifying a modulation method to be used is the first modulation method; and II. in a communication phase, communicating between said master and said slave(s) using: (a) said time slot specified by the information specifying said time slot to be used; and (b) said modulation method specified by the information specifying said modulation method to be used; and wherein, if the second modulation method is not specified by the information specifying said modulation method to be used, communicating using: (a) said time slot specified by the information specifying a time slot to be used; and (a) said first modulation method.