3.2 Receiver modules Figure 7 shows

3.2 Receiver modules
Figure 7 shows the block diagrams of the receiver for both audio and video signals. Two different types of PDs were used for the audio and video signals. For the audio part, the output of a low-speed PD (i.e., 15 Mb/s with a receiver sensitivity of −24 dBm) is first passed through the S/PDIF module followed by a high-quality stereo audio digital-to-analog converter (DAC) module. We have chosen a 192-kHz, 24-bit advanced segment stereo DAC for a high-quality audio signal. Filtering and amplification ensures the required audio output level. For the video link, a high-speed PD (i.e., 50 Mb/s with a receiver sensitivity of−17.5 dBm) followed by the PWM demodulator, a 3-MHz filter, and a video amplifier are used to recover the video signal. Figure 8 shows the audio and video receiver modules. There are a number of ICs available for the audio ADC. Here we have chosen a very simple chip (AK5386 from Asahi-Kasei, Chiyoda, Tokyo, Japan), which is a stereo A/D converter with a wide-ranging sampling rate from 8 to 216 kHz, widely used in both consumer and