Abstract: A stereo-audio video limited range low power RF transmitter to receiver system is provided transmitting signal from a video cassette recorder (VCR), satellite converter, TV camera, cable select box and a TV receiver/monitor, or VCR, utilizing a wireless signal path retaining signal quality normally associated with conventional wiring. Two-channel stereo-audio is passed via two independent audio channels matched to selected video channels for combined short range RF transmitter to receiver transmission to one or more television sets and/or VCR sets in different rooms, with at times display and/or recording simultaneously the same transmitted program from the transmitter of the system.

Abstract: A plurality of television signals are transmitted and selectively received on a single television channel allocation. Headend apparatus compresses a set of television signals, such as a main program signal and a plurality of different demographically targeted commercials. The plurality of compressed television signals are combined into a combined signal for transmission on a single television channel allocation. A receiver receiving the combined signal identifies characteristics of a television viewer, and selects a particular one of the compressed television signals from the received combined signal depending on the viewer characteristics. The retrieved signal is decompressed for use by a video appliance.

Abstract: A method for automatically selecting optimum frequencies for transmitting data from remote terminals upstream to a system manager is provided. The system manager initially selects a set of frequencies from a larger set of available frequencies and transmits a command downstream to each remote terminal indicating which frequencies to use. Each remote terminal transmits data messsages on each selected frequency in response to addressed commands generated by the system manager. The system manager receives and counts the data messages on each of the frequencies, and after a statistically significant number of messages are received, removes from use the frequency with the lowest number of data messages received. This frequency is replaced with either (1) a previously untried frequency, or if all frequencies have been tried, (2) a previously tried frequency with the highest number of data messages received.

Abstract: Bidirectional CATV (Cable Television) repeating amplifier circuitry has a first splitter, a second splitter, trunk distribution terminals used at a low level, and subscriber distribution terminals used at a high level. A distribution circuit distributes a signal from the first splitter to the distribution circuits and couples up-going signals from the distribution terminals and delivers the coupled signal to the second splitter.

Abstract: Fixed radio equipment serving as a base station includes a transmitter, a plurality of antennas, and a selective control circuit. The antennas are spaced apart from each other by a distance which minimizes a correlation of interferential fading. The transmitter modulates a carrier by identical signals to be transmitted during periods associated in number with the antennas and feeds the resulting bursts of the carrier time-serially to a selective control circuit. The selective control circuit delivers one of the successive bursts of the carrier fed from the transmitter to one of the antennas and then delivers another burst following the above-mentioned burst to another one of the antennas. Mobile radio equipment or station has a single antenna for receiving the identical signals transmitted time-serially from the base station. The mobile station selects and outputs either one of the received signals which has higher quality than the other.

Abstract: A baseband signal communication apparatus includes a transmission unit and a reception unit. The transmission unit superposes a subcarrier on one value of a baseband signal consisting of binary values, modulates a carrier with the baseband signal on which the subcarrier is superposed, and transmits the baseband signal as a transmission signal wave. The reception unit demodulates the baseband signal having the subcarrier superposed thereon by using a demodulator upon reception of the transmission signal wave, extracts the subcarrier from the demodulated signal by using a bandpass filter, and demodulates the baseband signal by causing a detector to detect an envelope of the subcarrier.

Abstract: Disclosed is an improved system for the delivery of entertainment and educational programming from a plurality of electronic libraries to a plurality of users. Users actuate a hand operated control device to: review a listing of available programming; enable the delivery of a program from a library; or control the delivery of forwarding and rewinding through the programming, and authorizing the purchase of advertised consumer goods by entering in personal identification numbers. The network of libraries and the paths for delivering the programming stored therein is arranged for optimum transmission efficiency and maximum access capacity. The key idea in optimizing transmission efficiency and access capacity is to recognize that programming can be grouped into different classes, and that not all classes of programs should be stored in all libraries.

Abstract: Automatic level calibration apparatus for transmitting data from a cable television terminal to the headend of a cable television system comprises programmable transmitter apparatus of the terminal, programmable receiving apparatus at the headend and a calibration controller. Responsive to an addressed command from the headend, the programmable transmitter apparatus returns a sequence of levels at a particular calibration frequency. The programmable receiver apparatus determines an indication of the received signal strength of each of the levels of the sequence of levels. The controller determines an optimum level for transmissions from the terminal.

Abstract: In a system including an originating source for providing multiple television programs to one or more local cable television systems for their distribution on a pay-per-view basis, data processing equipment at the originating source stores, for each local cable system, address information, information regarding which of the programs offered by the source it wishes to carry and the times it wishes to present each to its subscribers, and information identifying its addressable head-end equipment. The data processing equipment periodically assembles and communicates to all of the local cable systems, via a satellite channel independent from the channel used for communicating program signals, a binary message which contains address and program schedule information for each of the local cable systems.

Abstract: A cable television radio frequency data processor for receiving and processing data transmitted from a cable television terminal to the headend of a cable television system comprises a plurality of data receivers for receiving the returned data, detectors associated with each receiver for providing an indication of received signal strength and a data processor. The data processor responsive to the data receivers eliminates redundant data and collects statistics on data throughput and, responsive to the detectors, collects statistics on received signal strength. The data processor then may initiate recalibration of transmit signal levels or an appropriate selection of data transmit channels as required.

Abstract: A self contained tilt rack video cassette library cabinet containing multiple VCP units with an XYZ motion tape cassette selection and delivery system to computer directed insertion in a subscriber VCP and return after play to a tilt rack library storage bin. The system includes activation means, movie selection means and a TV set at each subscriber location, an address mechanism in the system and a telephone line connection through a duplex modem to a computer having a monitor and keyboard with computer controlling XYZ carrier movement pick up of cartridges from and return to video cassette storage bins, insertion and extraction of selected video cassettes to and from subscriber dedicated video cassette players (VCP). Each VCP has an audio and video output connection to respective modulators each output connected to a combiner mixer.

Abstract: A transmission line formed by a twisted pair of conductors with at least one input point for connection to a device for injection of a signal into the pair of conductors, and several output points for connection to devices for tapping of the signal transmitted on the pair of conductors. Each of the points has means for symmetrical tapping of the signal on the two wires of the pair. The tapping means has a high impedance with respect to the impedance of the pair of conductors, and is compatible with a multiple tapping of the signal on the pair of conductors. This transmission line permits the transmission of signals emitted in wideband, such as baseband video signals over distances of several hundreds of meters, with multiple tapping of a signal on one and the same line of the network, without causing any mismatching phenomena.

Abstract: An arrangement for supplying current to a wideband transmission cable includes an all-pass circuit having a high-pass path (VPH) and a low-pass path (VPB) in which the signals in the transmission cable are recombined by virtue of the presence of a phase inverter. A current supply supplies current to the transmission cable via a supply point situated in the low-pass path.

Abstract: A system and method for minimizing peak amplitudes and distortion in a communication system generating a composite signal. The present invention provides and maintains optimum phase conditions and a near-optimal set of auxiliary carriers in a closed-loop feedback system. An application to community antenna television (CATV) is disclosed.

Abstract: A community antenna broadcasting system comprises a transmitting center for broadcasting programs in physical channels, a transmission path, and one or a plurality of home terminals for receiving the programs broadcast from the transmitting center via the transmission path. The transmitting center transmits a main information which includes video and audio information for each of physical channels, and also transmits a control information which includes numbers of logical channels which are contents of the physical channels. The home terminal enters a supervision information which includes a number of a desired logical channel which corresponds to a desired program, and produces a channel selection instruction by collating the control information and the supervision information. A channel selection part is provided within the home terminal. The channel selection part receives the information via the transmission path and selects a physical channel in response to the channel selection instruction.

Abstract: A method of network management for a radio communications network comprising a plurality of stations each of which includes a transceiver and control means therefor, the transceiver and control means of the respective stations being substantially similar, and the stations being arranged to communication directly with any other station, the method comprising: assigning at least one control channel of predetermined frequency to the network for transmitting network control signals between the stations; assigning to each station which may assume control a ranking position in a priority list of stations which may assume control of the network; each station monitoring the control channel or channels to determine whether control has been established by another station, and if so accepting control signals from such other station, and if control has not been established, the station transmits at a time determined by the ranking position of the station control signals on said control channel or channels for assuming ne

Abstract: A spread spectrum communications system is described for recovering data from a signal having a first carrier frequency modulated by one of at least four phase modulations, each phase modulation orthogonal to one another and the signal further modulated by a predetermined spreading function incorporating a frequency synthesizer for generating a plurality of frequencies, including one of the phase modulations, a plurality of mixers, a combiner, a broadband convolver, a second combiner coupled to a reference signal generator for generating respective orthogonal modulations on spaced apart carrier frequencies, a power divider coupled to the output of the convolver and filters each having a frequency passband for recovering or separating the output signals of the convolver. The invention overcomes the problem of additional hardware complexity to accomodate Walsh orthogonal functions and of requiring a plurality of broadband convolvers to decode a plurality of orthogonal modulations of lesser bandwidth.

Abstract: An improved asymmetrical sideband amplitude modulation (AM) transmitter is provided wherein the resulting transmitted signal produces a pleasing pseudo-stereo effect when received by a stereo receiver of the type designed to receive symmetrical sideband, phase-separated AM stereo radio braodcasts, when such receiver is operating in its stereo mode.

Abstract: A process and apparatus for simultaneously broadcasting a first intelligence signal with a plurality of second intelligence signals is disclosed. The transmitter performs the following steps: multiplexing the plurality of second intelligence signals into a single signal to form a first modulating signal; frequency modulating a first radio frequency carrier signal with the first modulating signal to form a second radio frequency carrier signal; amplitude modulating the second radio frequency carrier signal using the first intelligence signal as a second modulating signal; and broadcasting the resultant single radio frequency signal out over a transmitting antenna.

Abstract: An AM stereo transmitter with bandwidth limiting utilizes the detection of high frequency energy in the modulating signal to control the difference channel input to the stereo encoder.

Abstract: An amplitude modulated radio transmission system is described which is compatible with conventional AM receivers. The transmitted signal comprises a carrier and two unequal amplitude sidebands. This signal can be received by receivers that are tuned to the carrier as well as receivers that are off tuned to favor the stronger sideband.

Abstract: In a system for frequency-diversity transmission, separate and distinct frequency carriers are obtained from the frequency modulation of an oscillator by a pure frequency with an index such that a certain number of Bessel lines thus obtained constitute a corresponding number of separate carriers. All the carriers are subsequently modulated by the information, then power-amplified in a single amplifier having a peak power equal to that of a single signal whose effective power would be the sum of those of the separate carriers. By means of this system, equipment for radio communication by tropospheric or ionospheric scatter propagation can be constructed in a simple manner and at low cost, with a high diversity order.

Abstract: Simulcast distortion in a receiver when using a same-frequency repeater is minimized by applying double modulation to a signal that is broadcast to the same-frequency repeater. A voice signal is applied without delay as AM on a carrier to a modulation index of up to 30%, and the same signal is also applied as FM on the same carrier with a time delay equal to the time delay in the same-frequency repeater. The same-frequency repeater detects the AM and applies the detected signal as FM on a carrier that is rebroadcast. Received FM signals are thus delayed by substantially the same amount whether they are received from the original broadcast or the same-frequency repeater.

Abstract: A radio controller for radio control of model vehicles and the like. The controller can be placed in a control mode wherein vehicle functions such as motor speed, direction, horn and lights are controlled by control signals. In addition, the controller can be placed in a voice transmission mode wherein an audio signal is transmitted to the vehicle and broadcast from a speaker mounted on the vehicle. The receiver of the radio controller is switched from the control mode to the voice transmission mode by way of the control signals. When the receiver is placed in the voice transmission mode, the control signals are ignored with switching to the control mode being accomplished by receiver circuitry which detects a momentary absence of the transmitted carrier signal.

Abstract: Apparatus is described for transmitting and receiving stereophonic broadcasts in the low frequency commercial AM broadcast band. A transmitter is described which modulates the phase and amplitude of a broadcast signal with separate information signals. A pilot tone may also be included to identify the transmission as stereophonic. Receiving means for detecting the PM and AM components to derive separate signals for stereophonic reception are included.

Abstract: A compatible AM stereo broadcasting system is disclosed in which the signal is a carrier having an amplitude directly variable with monoaural or sum (L+R) information, and having an instantaneous phase .phi. varying as a function of the resultant amplitude of the sum information (L+R) and difference information (L-R) which are established in a preselected phase relationship (quadrature). In a stereo receiver, L and R or the sum and difference signals may be restored by dividing the signal by the cosine of the angle .phi., and in a monaural receiver, the sum signal alone is detected.