Abstract: A system (10) for converting streaming digital data to frequency modulated data includes a digital decoder (12) providing content and associated data, a system controller (14) for formatting the associated data into frequency modulated sub-carrier data, and a frequency modulator (20) for modulating (24) the content and combining (25) the modulated content with a buffered version of the frequency modulated sub-carrier data. The streaming digital data can come from a satellite digital audio radio system receiver and the associated data can include at least one among a channel name, a channel number, an artist name, a song title, and traffic information. The system controller can format the associated data into an RDS Message format. The frequency modulator can include an RDS physical layer (32) and an RDS data link layer (30) that can generate a checksum. The frequency modulator can also include a register or buffer (28).

Abstract: A symbol detector (110) includes an analog-to-digital converter (115) for converting signal voltages to digital values and peak and valley counters (310, 315) for tracking the digital values to determine peak and valley values associated with high and low voltages of the signal. The symbol detector (110) further includes calculation circuitry (356) for calculating upper, lower, and center thresholds based on the peak and valley values and a decoder (125) for generating data symbols in accordance with the upper, lower, and center thresholds.

Abstract: A symbol detector (110) for generating data symbols from a received signal having multiple signal voltages comprises an analog-to-digital converter (115) for converting the multiple signal voltages to digital values and peak and valley counters (310, 315) coupled to the analog-to-digital converter (115) for tracking the digital values to determine peak and valley values associated with high and low voltages, respectively, of the received signal. The symbol detector (110) further comprises calculation circuitry (120) coupled to the peak and valley counters (310, 315) for calculating upper, lower, and center thresholds in accordance with the peak and valley values and a decoder (125) coupled to the analog-to-digital converter (115) and the calculation circuitry (120) for generating the data symbols in accordance with the digital values and the upper, lower, and center thresholds.