Method and system for generating a secret key from joint randomness

A wireless communication system for generating a secret key from joint randomness shared by a first wireless transmit/receive unit (WTRU) and a second WTRU, the system comprising:

• the first WTRU comprising:
• a first channel estimator for performing channel estimation to generate a first sampled channel impulse response (CIR) on a channel between the first WTRU and the second WTRU;
• a quantization unit for quantizing the first sampled CIR to generate quantized values;
• a source coding unit for performing source coding on the quantized values to generate a first set of bits;
• a error correction coding unit for generating a syndrome from the first set of bits;
• and
• a first privacy amplification unit for generating a secret key from the first set of bits;
• and
• the second WTRU comprising:
• a second channel estimator for performing channel estimation to generate a second sampled CIR on a channel between the first WTRU and the second WTRU;
• a decoder for generating a second set of bits from the syndrome received from the first WTRU and the second sampled CIR;
• and
• a second PA processor for generating the secret key from the second set of bits.

A method for separating estimated channel impulse response (CIR) into discrete multipath components in a wireless communication system, the method comprising:

• (a) generating a sampled CIR;
• (b) identifying a dominant multipath component;
• (c) performing a threshold test;
• (d) if the threshold test passes, outputting the identified dominant multipath component;
• and
• (e) if the threshold test does not pass, subtracting the identified dominant multipath component from the sampled CIR and returning to step (b) for identifying a subsequent multipath component.

An apparatus for separating estimated channel impulse response (CIR) into discrete multipath components in a wireless communication system, the apparatus comprising:

• a channel estimator for generating a sampled CIR;
• a threshold unit for performing a threshold test;
• and
• an orthogonal greedy algorithm (OGA) unit for iteratively performing a process for identifying a dominant multipath component while subtracting the identified dominant multipath component from the sampled CIR if the threshold test fails.