Invention:
Researchers at the University of Arizona have developed a novel spreading/address code family for high-speed, large-capacity wired/wireless or optical communications. The novel "transposed modified prime codes" (T-MPC) have specific correlation properties and flexible code size, length and weight. This code family is comparable to existing spreading code families in terms of correlations, bit-error rate (BER) performance and cardinality, but increases the cardinality up to twice that of existing prime code families. Thus, a greater number of users can be accommodated in the system. There is no time-shift feature in T-MPC as in MPC, so the code is not predictable and thus secure.
Background:
Multiple access techniques are required to meet the demand for high-speed and large-capacity communications in optical networks in which multiple users are allowed to share the network resources like bandwidth. Optical code-division multiple-access (OCDMA) is attractive due to its potential for enhanced information security, simplified network control, improved spectral efficiency and increased flexility in the granularity of bandwidth that can be provisioned.
Advantages:
- Greater number of users can be accommodated in the system
- Similar to prime codes: employment in a system running prime codes is non-destructive
- Compatible with low-weight prime codes
- Doubles the number of customers that can be carried
- Half the BER
Applications:
- Time-spreading synchronous code-division multiple-access (CDMA) techniques in electronics and optical communications
