Signal optimization of PSK modulated gold-sequences for narrow band transducers

Code division multiple access is a well-known method to minimize crosstalk between unsynchronized ultrasonic distance sensors. Thereby orthogonal signals are used which are generated by modulating orthogonal codes to a carrier signal. In this contribution PSK modulation is used to transmit gold sequences. Here narrow band air ultrasound transducers are used. Due to the limited bandwidth of the transducer there is a partial cross correlation between the electrical received signals. This can increase the error rate identifying the signals. By optimizing the modulation parameters the error rate can be reduced. Therefore the influence of an offset of the carrier frequency for different symbol lengths to the properties of the electrical received signals is investigated.