Implementing Elements of Regional Audio Technology

The device of zone selector includes control platform, interface module of central control terminal and power module with the core of FPGA chip. There are many logic modules in the chip, including audio input module, control input module, encoding module and decoding module.

The audio sampling module in the audio input module separates the audio clock Audio_CLK and transmits it to frequency doubling module. Based on Audio_CLK, the module generates multi-frequency clock signals and outputs the reference clock Ref_CLK_2 to the interface module of the control terminal of the zone selector.

The encoding module uses time-sharing multiplexing to encode audio data and control data into a set of composite data streams. The interface module of the central control terminal is equipped with two sets of bandpass filters and a coupled transformer T1. The differential output end is connected to the secondary winding of the coupling transformer T1 through a band-pass filter, and the central tap of the zone selector coupling transformer T1 is connected to the input end of the decoding module through another band-pass filter.