| 4790012 |
Encryption-decryption system |
| Dec-6-1988 |
In a data encrypting/decrypting system both the encoding and decoding stations are receptive of a common source of time varying digital signals. The digital signals in the encoding station are applied... |
| 4776012 |
Method of jumping composite PN codes |
| Oct-4-1988 |
The present invention is concerned with an apparatus and a method of jumping a composite PN code from a current phase position to a desired predetermined phase position so as to enhance acquisition of... |
| 4774716 |
Method for the transmission of digital data |
| Sep-27-1988 |
A method for the transmission of digital data by means of phase modulation (PSK) and "frequency hopping", in which symbols are transmitted several times in different transmission sections as synchronization... |
| 4761813 |
Military radar or radio communication system |
| Aug-2-1988 |
A military radar or radio communication system comprises, in particular, mobile transmitter-receiver apparatus wherein a plurality of operating frequencies are constantly changed in accordance with a frequency... |
| 4761796 |
High frequency spread spectrum communication system terminal |
| Aug-2-1988 |
The spread spectrum communication system terminal comprises a first subsystem including a first arrangement to encode a locally generally digital data with an error correcting code, a second arrangement... |
| 4759034 |
Multi-step spread spectrum communication apparatus |
| Jul-19-1988 |
In a pseudo-random communication system, a transmitter-generated encoded signal is to be correlated with a receiver-generated similarly encoded signal for recognizing synchronization of the transmitted... |
| 4754283 |
Codeless GPS sonde |
| Jun-28-1988 |
Windfinding apparatus is described in which receiver processing of the Global Positioning System (GPS) signals is without knowledge of the spread spectrum codes. The apparatus receiver ignores the bi-phase... |
| 4752939 |
Hidden preamble for frequency hopped synchronization |
| Jun-21-1988 |
A method is provided for achieving initial synchronization of the transmission and reception of a frequency hopped communication signal, which comprises the steps of transmitting a preamble defined by... |
| 4730340 |
Programmable time invariant coherent spread symbol correlator |
| Mar-8-1988 |
An hybrid array correlator is configured of a cascaded array of individually identical correlator cells, through which a preselectable reference symbol sequence, identifiable with a symbol to be acquired,... |
| 4716587 |
Broadband-signal broadcasting system |
| Dec-29-1987 |
A broadband signal broadcasting system comprising a circuit to encode video and audio signals forming a TV channel to be sent to a switching matrix, which is remotely operated by the subscriber; a circuit... |
| 4716574 |
Wirelessly functioning signal transmission system |
| Dec-29-1987 |
In a signal transmission system for broadband signals wherein the transmitting transducer and/or the receiving transducer has a non-isotropic radiation characteristic, properties of the received broadband... |
| 4706286 |
Method and circuit for extraction of Doppler information from a pseudo-noise modulated carrier |
| Nov-10-1987 |
A method and apparatus for detecting and identifying Doppler frequency and phase information contained within a signal of the direct sequence spread spectrum type. An incoming signal is split by a circuit... |
| 4694467 |
Modem for use in multipath communication systems |
| Sep-15-1987 |
A modem in which the transmitter uses spectrum spreading techniques applied to sequentially supplied input bits, a first group thereof having one spread spectrum sequence characteristic and a second group... |
| 4688251 |
Wave packet communication subsystem for determining the sync pulses and correlating the data pulses of a wave packet |
| Aug-18-1987 |
A subsystem of a wave packet communication system uses the same sets of receivers and correlators to detect both the sync pulses and the messages carried by different wave packets. The system does this... |
| 4685132 |
Bent sequence code generator |
| Aug-4-1987 |
A method and apparatus for generating a bent sequence code as a transform of an m-sequence code. |
| 4669089 |
Suppressed clock pulse-duration modulator for direct sequence spread spectrum transmission systems |
| May-26-1987 |
In the disclosed digital circuit, a digital direct sequence modulation signal is converted to a suppressed clock pulse-duration modulation signal to thereby suppress the clock feature in the frequency... |
| 4658436 |
Disguised transmission system and method |
| Apr-14-1987 |
Data signals are transmitted at a variable information rate with variable power so the transmitted information rate and transmitted power level increase and decrease together to simulate high frequency... |
| 4654705 |
Two channel audio scrambling system |
| Mar-31-1987 |
A two channel audio scrambling circuit for a television signal encoding system includes synchronized digital carrier switching means for deriving two suppressed carrier, switched audio signals that are... |
| 4653069 |
Spread spectrum correlation receiver |
| Mar-24-1987 |
A spread spectrum communication system having a correlation receiver for decoding an information signal transmitted on a pseudo-noise (PN) carrier. The receiver synchronizes to the transmitted signal by... |
| 4630283 |
Fast acquisition burst mode spread spectrum communications system with pilot carrier |
| Dec-16-1986 |
A high frequency code division multiple access spread spectrum (CDMA SS) communications system includes multiple transmitters and their associated receivers, and a pilot carrier source. In order to reduce... |
| 4630282 |
Frequency-hopping digital data link |
| Dec-16-1986 |
Ordinary digital data is reformed and time shifted such that it may be broadcast over a radio link which periodically shifts its frequency. The system of this invention utilizes timing information obtained... |
| 4606040 |
Transmitting-receiving station for a system for transmitting data by frequency hopping |
| Aug-12-1986 |
A transmitting-receiving station for transmitting information by frequency hopping comprises a code generator to define the use of a plurality of channels in accordance with a high-speed skip law for a... |
| 4578817 |
Method for establishing communications in a network of frequency-jumping transmitter-receiver stations and a station for the utilization of said method |
| Mar-25-1986 |
In order to establish communications in a conference network of transmitter-receiver stations, each station establishes a frequency-jumping standby law while a calling station transmits a frequency-diversity... |
| 4550222 |
Process for interception-protected frequency band compressed transmission of speech signals |
| Oct-29-1985 |
In order to achieve a good masking, together with minimum bandwidth requirement of sample values of spectral channels which are to be transmitted in the timing of consecutive analysis intervals in a time... |
| 4530008 |
Secured communications system |
| Jul-16-1985 |
Apparatus and method for reducing the cost and complexity of equipment placed on subscribers' premises in a subscription communications system, such as a cable television system, while at the same time... |
| 4479226 |
Frequency-hopped single sideband mobile radio system |
| Oct-23-1984 |
The present invention relates to a frequency-hopped single sideband (SSB) mobile radio system implemented by hopping the carrier frequency of an input signal (s(t)) every .tau. seconds. The hopping is... |
| 4476566 |
Frequency hopping radio communications apparatus having pseudo-random _channel selection |
| Oct-9-1984 |
Channel selection in a frequency hopping radio set is controlled by a pseudo-random number generator, the pseudo-random number being used to address an N bit memory (3) which is used to identify each of... |
| 4475208 |
Wired spread spectrum data communication system |
| Oct-2-1984 |
A wired spread spectrum data communication system includes a modulator and a demodulator coupled to a transmission line having other signals thereon. The modulator includes a pseudo-noise (PN) generator... |
| 4454604 |
Virtual time base direct synchronizer and method therefor |
| Jun-12-1984 |
A system for virtual time base direct synchronization in which a hopping sequence signal grossly synchronized with a received hopped base band has a fine synchronization correction performed by a virtual... |
| 4442527 |
Synchronization systems |
| Apr-10-1984 |
A syncrhonization arrangement is disclosed for synchronizing a receiver with a transmitter whose frequency is hopping through a sequence of predetermined frequencies arranged pseudo-randomly. The transmitter... |
| 4425661 |
Data under voice communications system |
| Jan-10-1984 |
A communications system capable of simultaneously transmitting voice and data information. The spectral energy of the data signal is smeared by spreading it in a spectrum with energy packed in the lower... |
| 4398062 |
Apparatus for privacy transmission in system having bandwidth constraint |
| Aug-9-1983 |
Source intelligence within a predetermined bandwidth is normally provided to a transmission channel having a bandwidth constraint of the predetermined bandwidth. For privacy transmission, a first pulse... |
| 4392241 |
Digital interface system |
| Jul-5-1983 |
A system interfaces classified information for encryption and transmission over ultra high frequency (uhf) or high frequency (hf) bands and for receiving and decryption of uhf and hf information for relay... |
| 4383323 |
Spread spectrum FH-MFSK transmitter and receiver |
| May-10-1983 |
The present invention relates to transmitters (10) and receivers (30) for use in a spread spectrum radio communication system wherein transmitters generate FH-MFSK signals by adding elements of each user's... |
| 4361890 |
Synchronizing system |
| Nov-30-1982 |
1. In a communication system utilizing at least two independent binary coded pulse signal sequences, means for achieving and holding time synchronism between said two sequences which comprises the combination... |
| 4351064 |
Communication |
| Sep-21-1982 |
There is disclosed frequency modulation (FM) or phase modulation (PM) communication with a receiver having a limiter, in spread-spectrum operation for security purposes. The spectrum is spread on transmission... |
| 4334322 |
Communication management system for providing antijam/privacy capabilities for voice radio communications |
| Jun-8-1982 |
A communications management system includes a central processor (10) which is connected via an order wire subsystem (12) to various remote terminals (14, 16, 18). The central processor (10) maintains tables... |
| 4329711 |
Apparatus for encoding of information |
| May-11-1982 |
Information encoding apparatus comprises at least two modulators, each operating on a different channel, means for combining the outputs of the modulators, means for applying an information signal to the... |
| 4326292 |
Random energy communication system |
| Apr-20-1982 |
5. An intelligence communication system comprising a transmitter and a receiver; said transmitter comprising means for obtaining a relatively wide band random energy carrier signal, means for modulating... |
| 4324002 |
Delay-modulated random energy intelligence communication system |
| Apr-6-1982 |
1. An intelligence communication system comprising a transmitter and a receiver; said transmitter comprising non-periodic energy means for generating a carrier, means for effecting a change in the time... |
| 4320514 |
Spread spectrum FH-MFSK radio receiver |
| Mar-16-1982 |
The present invention relates to a spread spectrum, FH-MFSK radio receiver capable of demodulating and decoding one or more concurrently received L-length frequency-hopping, Q level frequency shift keyed... |
| 4312072 |
Radio frequency transmission system |
| Jan-19-1982 |
Radio transmission system in which the carrier frequency oscillator at the transmitter is wobbulated by varying its frequency in a periodic manner and modulated and transmitted to a receiving site where... |
| 4308617 |
Noiselike amplitude and phase modulation coding for spread spectrum transmissions |
| Dec-29-1981 |
A plurality of binary pseudo noise generators are used to develop a Gaussian code that appears thermal noiselike in both amplitude and phase. Half of the pseudo noise generators are provided in an in-phase... |
| 4276652 |
Secure communication system with improved frequency-hopping arrangement |
| Jun-30-1981 |
A signal scrambling system of the type in which the frequencies of the information signal band are inverted by heterodyning the information signal with a varying beat frequency. In accordance with the... |
| 4255810 |
Jam resistant frequency modulation system |
| Mar-10-1981 |
1. An interference proof FM video communication system comprising: means for frequency modulating a carrier frequency by a video signal; means for bi-phase modulating the output of said frequency modulating... |
| 4244053 |
Privacy communication method and system |
| Jan-6-1981 |
A privacy communication method and system which utilizes coherent, continuously changing frequencies for keyed, pulsed, and voice communications. A synthesized swept frequency or "chirp" signal imparts... |
| 4241447 |
Secure spread spectrum communication system |
| Dec-23-1980 |
A communication system is protected against jamming by modifying a conventional spread spectrum communication system by inserting errors, in the form of digital noise, into the pseudo-noise digital code... |
| 4231113 |
Anti-jam communications system |
| Oct-28-1980 |
Binary information signals which are to be transmitted are combined with a pseudo-random signal wave form such as a pseudo-random sequence of binary bits. Each binary message element, whether a binary... |
| 4193030 |
Frequency hopping communication system |
| Mar-11-1980 |
A signal modulated with information is hopped to discrete frequencies and its phase is selected to be 0.degree. or 180.degree. in each frequency hop interval under control of a pseudo noise binary code... |
| 4185241 |
Communications system using time position modulation and correlation slope demodulation |
| Jan-22-1980 |
An angle modulation radio communications system having privacy and security characteristics. The system utilizes two or more communication units, one at the transmitting terminal and the other at the receiving... |
