Wireless digital transmission system for loudspeakers
View Patent ↗This invention relates to a wireless digital transmission system for loudspeakers comprising: compression means for the file representing the digital audio signal of the “compact disc” type, a transmission device comprising means of converting this compressed signal into a series signal moving by packets going to a modulator circuit with phase quadrature and means of transmitting the signals exiting the modulator circuit with phase quadrature to the domestic network for feeding electricity; a receiving device comprising means of connecting to this domestic network and of extracting from the feed electrical signal, by a demodulator with phase quadrature, data packets moving the digital audio signal to convert it into a parallelized digital signal sent to a decompression circuit; means of converting the decompressed digital signals into an analog signal intended to feed a loudspeaker after adequate amplification.
1. A digital transmission system for playing music through audio speakers which uses AC power lines as an audio network, comprising:
a digital compression device for compressing digital music data into a compressed digital music data;
a digital transmission device including a series conversion circuit for converting the compressed digital music data into series compressed digital signal packets;
a digital modulator which controls a transmitter for transmitting the series compressed digital signal packets onto the AC power lines using one carrier frequency; and
a digital receiver device connected to the AC power lines for receiving the transmitted packets over the AC power lines, wherein the digital receiving device includes:
a digital demodulator for demodulating the series compressed digital signal packets modulated on one carrier frequency;
a serial/parallel digital converter for converting the demodulated series compressed digital signals into demodulated parallel compressed digital signals;
a digital decompressor for decompressing the demodulated parallel compressed signals into demodulated parallel decompressed digital signals;
a digital/analog converter for converting the demodulated parallel decompressed digital signals into analog signals; and
a loudspeaker for receiving the analog signals and generating music corresponding thereto;
wherein the series conversion circuit is operable to encode a destination address into the series compressed digital signal packets, and further wherein the digital receiving device is operable to compare the destination address to an address of the receiving device in order to determine if the signal is addressed to the receiving device.
2. The digital transmission system of claim 1 , wherein the digital modulator is a phase quadrature digital modulator.
3. The digital transmission system of claim 1 , wherein the series conversion circuit is operable to multiplex several digital files representing a different music signal intended for reception by various receiving devices having different addresses associated therewith.
4. The digital transmission system of claim 1 , wherein the transmitter comprises an encryption device which encrypts the digital signal, and the receiving device includes a decryption circuit which uses a decryption key to decrypt the encrypted digital signal.
5. The digital transmission system of claim 4 , wherein the digital signal is serialized according to a protocol including a part for starting protocol data, a part for an address of an intended recipient, a part for digital signal or multiplexed digital signal, and a part for ending protocol data.
6. The digital transmission system of claim 5 , wherein the protocol further includes part for control data for the loudspeaker.
7. The digital transmission system of claim 6 , wherein the protocol further includes a part for an encryption key for use in decrypting the digital data.
8. The digital transmission system of claim 5 , wherein the protocol further includes a part for an encryption key for use in decrypting the digital data.