Abstract: A system and method are provided for synchronizing a reference clock to a pseudorandom non-return to zero (NRZ) data stream in a clock data recovery system. The method comprises: sampling a pseudorandom NRZ data stream; determining a mean frequency of transitions (Fd) in the data stream; determining a transition probability (P) associated with the mean frequency of transitions; using a phase/frequency detector responsive to a VCO frequency, the mean frequency of transitions, and the transition probability; in response to using the phase/frequency detector, supplying a voltage controlled oscillator tuning voltage; generating the VCO frequency responsive to the tuning voltage; using a XOR phase detector to compare the VCO frequency to the NRZ data stream; in response to using the XOR phase detector, supplying a voltage controlled oscillator tuning voltage; and, generating the VCO frequency responsive to the tuning voltage.

Abstract: A system and method are provided for measuring pseudorandom non-return to zero (NRZ) data rates in a communications device integrated circuit (IC). The system comprises a transition detector to sample a pseudorandom NRZ data stream and to supply a mean frequency of transitions (Fd). A probability analyzer receives the mean frequency of transitions, compares the mean frequency of transitions to a transition probability (P), and supplies a derived mean data stream rate (B), where B=Fd/P. In some aspects of the system, a gating circuit is included to supply a gate time period (Td). Then, the probability analyzer receives the gate time period, compares a mean transition count of the mean frequency of transitions to a transition probability (P), and supplies a compensated transition count (Nc), where Nc=Np/P. A system for selecting the frequency range of a VCO, for use in pseudorandom NRZ communications, is also disclosed.

Abstract: A blasting mat made up of arcuate vehicle tire members arranged in hinged together groups. The mat has rigid joining means along its sides permitting the mat to be hingedly joined side-by-side with other mats to form a larger protective cover. The mat has means for protecting the joining means from damage during blasting.