Method of Implementing a UART Using Digital Signal Processing Techniques
Original Publication Date: 1989-May-01
Included in the Prior Art Database: 2005-Jan-28
Traditional UART (universal asynchronous receiver transmitter) receivers perform rapid binary (one bit) sampling of an input data stream. The sampling rate is typically 10-20X the actual bit rate. The resultant sample stream is examined to extract data. Oversampling is required in order to get accurate start bit location estimates. The accuracy of the start bit location estimate has a substantial influence on the error rate performance of a UART when the 0/1 timing is asymmetric. When a modem is designed using digital signal processing, this oversampling process can require an excessive amount of processing power. This method seeks to reduce the processing power without reducing the performance of the UART.