Patent ID: 7116709

Claim:
A communication method for transmitting information by a wave form combined with either a first wave form or a second wave form, using a first waveform and a second waveform, wherein said combined plurality of waveform patterns has transitions of any one of rising edges and falling edges in approximately equi-intervals, wherein said combined plurality of waveform patterns keeps a constant duty independently of data signals to be communicated, and wherein in such a case that an observation is made of said combined waveform which is filtered by a low-pass filter at timing of said transitions, different logic levels can be monitored as to said first waveform and said second waveform, wherein said first waveform representing one level of data signal and said second waveform representing another level of data signal are formed by a combination of a plurality of wave form patterns having at center portions thereof, a transition of any one of a rising edge and a falling edge, and wherein for data communication carried out by employing said first waveform and said second waveform, said data communication is performed in such a manner that said one transition does not occur except for at center portions of the waveform patterns.