Abstract: A framer is adapted for framing a high error rate data signal received through a link of a communications network, the data signal comprising M (an integer, M>1) interleaved sub-streams. The framer includes means for detecting a respective unique synchronizing word within each sub-stream. Each respective unique synchronizing word comprises: a non-unique position word having a first predetermined hamming distance; and a non-unique identifier word having a second predetermined hamming distance. The framer preferably includes M individual framers, and a master framer. Each individual framer operates to search the data signal to detect a respective one of the respective unique synchronizing words; and assert a respective individual frame found state for a first predetermined period of time when a respective one of the unique synchronizing words is found.

Abstract: At a transmitter, a measurement array is constructed from various combinations of frame bits, including at least one combination Which includes many frame bits and at least one combination which includes only a few frame bits. The measurement array is transmitted along with the frame bits. Upon receipt of the frame at a receiver, a parity check is performed on the received frame bits and on the measurement array, resulting in the creation of a symptomatic array. The symptomatic array can be accumulated during the course of successive frames. After a sufficiently high number of frames, it will become clear from the values of the elements in the accumulated symptomatic array which bits in the symptomatic array are saturated and which are not. The accumulated symptomatic array is then mapped to a BER estimate.

Abstract: A coupled oscillator arrangement is provided comprising first and second VCOs (voltage controlled oscillators), and a bi-directional interconnect which injection locks the first and second VCOs to each other. Advantageously, this provides a mechanism which effectively eliminates the phase jitter between the phase of first and second VCOs which makes them suitable for use in a diversity receiver, while at the same time providing a redundancy arrangement in which the failure of one of the VCOs does not effect the functionality of the other. The use of a bi-directional interconnect minimizes the complexity and cost of coupling the two VCOs. Preferably, the bi-directional interconnect injects a first signal representative of an output signal of the first VCO to the output of the second VCO and injects a second signal representative of an output signal of the second VCO to the output of the first VCO.