Abstract: A receiver for recovering serial digital data, such as teletext, achieves an effective sampling rate which is a multiple of the local receiver clock frequency by passing the data signal through a multi-tap delay line. The delay line outputs are supplied to a register, and the register output which yields the lowest bit error rate is determined and used as the data sampling point. The optimum sampling point is determined by first ascertaining a nominal sampling point from the signal preamble and then programmatically incrementing through the available sampling points (register outputs) until there is no improvement in bit error rate.
Abstract: A receiver for recovering serial digital data, such as teletext, achieves an effective sampling rate which is a multiple of the local receiver clock frequency by passing the data signal through a multitap delay line. The delay line outputs are supplied to a register, and the register output which yields the lowest bit error rate is determined and used as the data sampling point. The optimum sampling point is determined by first ascertaining a nominal sampling point from the signal preamble and then programmatically incrementing through the available sampling points (register outputs) until there is no improvement in bit error rate.