Kabushikikaisha Kenwood

Nippon Hoso' Kyokai

Trio Kabushiki Kaisha

Hirokazu Kobayashi

Yukihiko Miyamoto

Hiroshi Miyazawa

Syuichi Fujisawa

Masaoki Takai

Kenichi Shiraishi

Syoichi Suzuki

In one way address transmission system of a PCM music broadcasting, a plurality of the PCM signals are time divisionally multiplexed and then the multiplexed data is scrambled for transmission. An address code in the transmitted scrambled data is arranged so that only the contracted receiver can descramble the address code.

One-way address transmission system of PCM music

A time division multiplex transmission system includes: a time division multiplex encoder for supplying a master clock to a plurality of PCM digital signal sources having a same sampling requency and a same quantization bit number to effect clock synchronization and generating a time-divisionally multiplexed data signal based on a data word not D/A converted and sampled from each digital signal source; a transmission line for transmitting the multiplexed data signal from the time division multiplex encoder; and a time division demultiplex decoder for selecting a desired transmitted, multiplexed data signal and demultiplexing the selected data signal in accordance with a transmission rate before the time division multiplexing.

TDM transmission system

An addressable PCM music broadcast receiver which decodes a contraction identification code such as an address code allocated to the receiver and transmitted by a broadcasting station which performs a pay PCM music broadcast. The receiver is capable of receiving a contracted broadcast or channel on the basis of the decoded result. The receiver further has a demonstration function of receiving a non-contracted broadcast or channel for only a given time.

Addressable PCM music broadcast receiver

In multi-channel PCM music broadcasting system, a plurality of blocks are time division multiplexed, each block having at least one music channel for a PCM formatted music signal and having an independent operation mode information. The time division multiplexed signal modulates a carrier, and a plurality of time division multiplexed signals each having a frequency shift from the carrier are frequency division multiplexed for transmission. The operation mode information for the plurality of blocks is collectively inserted in a time division multiplexed frame, an operation mode information for the plurality of time division multiplexed signals each having a frequency shift is exchanged among a plurality of time division multiplexing units, and both the operation mode informations are commonly inserted in the time division multiplexed frame for transmission. Upon designation of a music channel at a receiver side, both the operation mode informations are referred to to select a particular frequency and block including the designated music channel.

Multi-channel PCM music broadcasting system

A time division multiplex transmission system includes: a time division multiplex encoder for supplying a master clock to a plurality of PCM digital signal sources having a same sampling frequency and a same quantization bit number to effect clock synchronization and generating a time-divisionally multiplexed data signal based on a data word not D/A converted and sampled from each digital signal source; a transmission line for transmitting the multiplexed data signal from the time division multiplex encoder; and a time division demultiplex decoder for selecting a desired transmitted, multiplexed data signal and demultiplexing the selected data signal in accordance with a transmission rate before the time division multiplexing.

A time division multiplex transmission system for time division multiplexing a plurality of information signals having different sampling frequencies and transmitting the time division multiplexed signal by one transmission path. The system includes the steps of: rearranging the plurality of information signals so as to have a format of the time division multiplexed signal by use of a reference sample signal which has a frequency obtained by multiplexing the maximum frequency or a frequency higher than the maximum frequency among the sampling frequencies of the plurality of information signals by the number of the plurality of information signals; and interposting a dummy signal into the portion where there is no available information signal.

Method and apparatus for multiplexing of input signals having differing

A frequency synthesizer includes a 1/N divider for generating an address clock signal the frequency of which is 1/N times the frequency of an input signal, a memory for storing samples in a unit sine and cosine wave which is read out in response to the address clock signal to produce a frequency deviation signal, and a quadrant modulator responsive to both of the input signal and frequency deviation signal for producing an output signal the frequency of which is the difference between the input signal and frequency deviation signal. The frequency of the frequency deviation signal is varied by digitally changing N to modify the frequency of the output signal while maintaining the continuousness of the output signal phase.

Frequency synthesizer suited for use in a time division multiplexing

A time division multiplexed signal demultiplexing system for regenerating original signals from a time division multiplexed signal which is obtained by time-division multiplexing information signals of N channels with mutually different sampling or clock frequencies by means of a reference clock signal of a frequency equal to N times of the highest one of the sampling or clock frequencies or an even higher frequency and inserting a dummy signal and a dummy flag bit in pairs in the portion where the information signal is lacking.

Growing community of inventors

Urawa, Japan

Hirokazu Kobayashi