Secured scrambling codes for vehicular control and navigation

The intent of the paper is to propose a new set of scrambling codes at the physical layer in a manner that provides much higher security and reliability. In Vehicular Communication system at the physical layer the neighboring node search procedure consist of series of synchronization stages by which the client determines time and frequency parameter necessary to demodulate the downlink and to transmit uplink signals with correct timing. This critical exchange makes the physical layer elements vulnerable to possible security related attacks by undesired entities. At present the popular standards use binary Gold as scrambling sequences for the control channel. Gold codes are known to provide good correlational properties but lack severely in other areas like cardinality. This paper suggests the use of De Bruijn sequences as next generation set of scrambling codes especially for their huge cardinality and correlation related properties. Performance of binary modified De Bruijn codes is analyzed with a specifies emphasis on length 31 so as to compare it with the Gold codes of length 31 currently suggested by the standard. De Bruijn sequences are seen to provide much more favorable results as compared to Gold codes.