| 摘要 |
Method and apparatus for providing a FSK data slicer for use in wireless telecommunications such as cordless telephones. The FSK data slicer is used by a receiver circuit in a wireless telecommunication device for converting an analog data signal to a digital data signal. Furthermore, the FSK data slicer responds to different mode of the analog data signal. The FSK data slicer includes a low-pass filter, a controller, a comparator, and an integrator. The low-pass filter receives the analog data signal for generating a median voltage, or slice voltage. Furthermore, the low-pass filter includes connectors to allow an external resistor to be serially connected between the filter input and the analog data signal and to allow an external capacitor to be connected in parallel with the slice voltage at the filter output. The bandwidth of the low-pass filter is controlled by the controller. The controller responds to specific intervals of the TDD frames, initial acquisition of data in the analog data signal, and known characteristics of the TDD frames and adjusts the low-pass filter bandwidth, accordingly. As a result, the low-pass filter drives the slice voltage only when it can do so accurately, and drives it strongly when the slice voltage will be very accurate. The comparator receives and compares the analog data signal and the slice voltage in order to produce a digital data signal. The digital data signal is then sent to the integrator, which over-samples each data bit of the digital data signal. The over-sampling is concentrated on the middle three quarters of each data bit, thereby ensuring the highest level of reliability.
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