Patent ID: 9065708
Filing Date: 2015-06-23
Classification: H04L

Abstract:
1. An apparatus of transmitting additional information to a preamble of a packet in differential modulation packet data communication, the apparatus comprising: a phase rotator that outputs a phase rotation quantity corresponding to additional information to be applied to a transmission target packet; a transmission-multiplier that multiplies the phase rotation quantity output from the phase rotator by a preamble to be transmitted; a symbol mapper that converts header and payload data to be applied to the transmission target packet into symbols and outputs the same; a multiplexer that processes an output signal of the transmission-multiplier and an output signal of the symbol mapper to be selectively output through an output end to form a symbol stream in units of packets; and a differential symbol converter that converts the symbol stream output from the multiplexer according to a predetermined differential modulation method and outputs the converted symbol stream, wherein the phase rotator selects one phase rotation quantity corresponding to the additional information to be applied to the transmission target packet among four different phase values and outputs the selected phase rotation quantity, and thereby 2-bit additional information is loaded on the preamble.