METHOD OF PROTECTING A FREQUENCY OF A DATA STREAM FROM INTERFERENCE AND CIRCUIT PERFORMING SUCH A METHOD

摘要

A method for mixed analog digital designs protecting the frequencies that are important for the analog part. The generated digital data stream has relatively large signal levels compared to the sensitive analog parts. The data bit stream is monitored and their frequency spectrum is corrected. The monitoring is performed by a conversion receiver that is adapted to sample the spectrum in a protected band and to generate an I and Q signal. A correction signal is obtained by multiplying the I and Q signal by the protected frequency. The spectrum is corrected by using the correction signal to generate small shifts in the edges of the data bit stream.