摘要 |
PURPOSE: A selective frequency modulating apparatus using a re-spreading code and a method thereof are provided to use an orthogonal code with a high spreading rate, thereby increasing the processing gain of the entire system. CONSTITUTION: A serial-parallel convertor converts transmission data serially or in parallel according to a preset ratio. At least one sub frequency selective spreading device(121~123) selects one spreading code using a data bit inputted from the serial-parallel convertor. A multi value selecting unit(130) selects multi values in at least one spreading code. The first XOR logic circuit(140) re-spreads a selective frequency baseband into a selective frequency transmitting band by XOR-operating the output of the multi value selecting unit with a re-spreading code, Wn. |