Patent ID: 8478133

Claim:
A method for encoding and decoding of signals using a) a transmitter capable to generate an optical signal when subject to an electric signal, and b) a receiver capable to generate an electric signal when subject to an optical signal; wherein a multi-level encoding of optical signals is used, wherein said transmitter is capable to generate i) “zero” signal, which means no optical signal, ii) an optical pulse having a first duration, and iii) an optical pulse having a second duration, wherein said second duration is longer than said first duration, and wherein said transmitter is fast and said receiver is slow such that a response time of said receiver exceeds said first duration of said optical pulse generated by said transmitter; and wherein an electric signal generated by said receiver as the response to the optical pulse having said first duration has a first amplitude, and wherein an electric signal generated by said receiver as the response to the optical pulse having said second duration has a second amplitude, and wherein said second amplitude is larger than said first amplitude.