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3601 results about "Spread spectrum" patented technology
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In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth. These techniques are used for a variety of reasons, including the establishment of secure communications, increasing resistance to natural interference, noise and jamming, to prevent detection, and to limit power flux density (e.g., in satellite down links).
Method of interference management for interference/collision avoidance and spatial reuse enhancement
InactiveUS20050058151A1Improve rendering capabilitiesImprove channel utilizationEnergy efficient ICTPower managementDifferentiated servicesDifferentiated service
A method called the evolvable interference management (EIM) method is disclosed in this patent for avoiding interference and collision and increasing network throughput and energy efficiency in wireless networks. EIM employs sensitive CSMA / CA, patching approaches, interference engineering, differentiated multichannel, detached dialogues, and / or spread spectrum techniques to solve the interference and QoS problems. EIM-based protocols can considerably increase network throughput and QoS differentiation capability as compared to IEEE 802.11e in multihop networking environments. Due to the improvements achievable by EIM, the techniques and mechanisms presented in this application may be applied to obtain an extension to IEEE 802.11 to better support differentiated service and power control in ad hoc networks and multihop wireless LANs. New protocols may also be designed based on EIM.
Owner:YEH CHIHSIANG
High data rate wireless packet data communications system
InactiveUS6894994B1Easy to deployEasy to upgradeError prevention/detection by using return channelNetwork topologiesTransceiverModem device
A wireless packet data communications system that includes a number of modem pool transceivers (MPTs), one or more modem pool controllers (MPCs), and one or more servers. Each MPT receives and processes data packets to generate a modulated signal (e.g., a CDMA spread spectrum signal) suitable for transmission over a terrestrial communications link. Each MPC provides call related processing for one or more MPTs. The servers couple to the MPTs and MPCs via an Internet Protocol (IP) back-bone and provide management of the communications system. The IP back-bone further interconnects the MPTs with one or more data networks and includes a number of routers that route data packets between the data networks and the MPTs. Each MPT can couple to two or more routers for redundancy. Each MPT is operated as an element in an IP network and is associated with an IP address that identifies the MPT. One to three MPTs can be deployed at each cell site to provide wireless data service coverage for up to three sectors at the cell site. The MPCs can either be centralized and coupled to the MPTs via the IP back-bone or distributed about the communications system.
Owner:QUALCOMM INC
Method and apparatus for information conveyance and distribution
InactiveUS20040054425A1Sufficient signal to noise ratioReduce distortion problemsComputer controlElectromagnetic transmissionLow distortionSpread spectrum
The method and apparatus for information conveyance and distribution to bidirectionally focus or guide a wide spectrum of electromagnetic waves propagated over a possible variety of propagation media, including free space or wireless, surface wave, and cable or wired transmission lines. The apparatus communicates with information devices immediately adjacent to these media wherein the devices, which are not themselves part of the apparatus, may have electromagnetic access to one another. The apparatus maintains adequate signal to noise ratio and low distortion for a possible variety of different signal modulation and encoding types which it can support while permitting transparent, simultaneous communications among a variety of devices. Spread spectrum techniques may be used within the apparatus to mitigate propagation medium distortions and impairments as well as to control access and provide a means for securing information within the corridor and for obtaining revenue. Adapters may be employed to provide either full or half duplex access to the information devices which utilize it.
Owner:CORRIDOR SYST INC
System and method for monitoring remote devices with a dual-mode wireless communication protocol
ActiveUS20050195775A1Electric signal transmission systemsNetwork traffic/resource managementWireless transceiverTransceiver
The present invention is generally directed to systems and device for monitoring remote device with a wireless, dual-mode communication protocol. As such, a representative embodiment is a system for monitoring and controlling remote devices. The system includes a first- and a second remote device; and a first and a second wireless transceiver integrated with the respective remote devices. The wireless transceivers are configured to communicate with at least one of a spread-spectrum communication protocol and a fixed-frequency communication protocol.
Owner:STATSIGNAL IPC
Method and system for a remote downlink transmitter for increasing the capacity and downlink capability of a multiple access interference limited spread-spectrum wireless network
InactiveUS7061891B1Increased cost-effectivenessIncrease speedData switching by path configurationRadio transmissionCellular architectureEffective solution
The present invention relates to a system and method for extending the coverage area and communication capacity of a spread-spectrum based wireless network. The system comprises a unique dual-scale, asymmetrical cellular architecture for a wireless network, wherein the communication uplink is based on a macro-cellular system, and the communication downlink is based on a micro-cellular system. Through the user of remote downlink transmitters in the micro-cellular system, the present invention provides a cost effective solution for increasing communication capacity, extending coverage area, and providing high speed communication downlink.
Owner:LEIDOS
Presswork encryption security printing technology based on multi-system quadrature amplitude modulation
InactiveCN101777134ACombating Illegal CopyingStrong anti-counterfeiting abilityVisual presentationElectronic documentSecurity printing
The invention discloses a presswork encryption security printing technology based on multi-system quadrature amplitude modulation. By adopting the security printing technology, a paseudorandom modulating signal can be generated from anti-counterfeiting information through spread spectrum, encryption and channel coding, the anti-counterfeiting information can be embedded into a whole page through a multi-system quadrature amplitude modulation (QAM) mode, and the anti-counterfeiting information can be identified from any fragment in presswork identification. The invention has very strong smash-resistance, can effectively resist piracy behaviour based on cameras, scanners, electronic documents and the like, and can be widely applied to the field of presswork anti-counterfeit.
Owner:BEIJING INSTITUTE OF GRAPHIC COMMUNICATION
Base station identification in orthogonal frequency division multiplexing based spread spectrum multiple access systems
InactiveUS6961364B1Radio transmission for post communicationMulti-frequency code systemsFrequency shiftSpread spectrum
A base station having the strongest downlink signal is identified by utilizing a unique slope of a pilot tone hopping sequence being transmitted by a base station. Specifically, base station identification is realized by determining the slope of the strongest received pilot signal, i.e., the received pilot signal having the maximum energy. In an embodiment of the invention, the pilot tone hopping sequence is based on a Latin Squares sequence. With a Latin Squares based pilot tone hopping sequence, all a mobile user unit needs is to locate the frequency of the pilot tones at one time because the pilot tone locations at subsequent times can be determined from the slope of the Latin Squares pilot tone hopping sequence. The slope and initial frequency shift of the pilot tone hopping sequence with the strongest received power is determined by employing a unique maximum energy detector.
Owner:QUALCOMM INC
Full-Field Light Detection and Ranging Imaging System
Apparatuses and methods determine positional information from a reflected optical signal for an object on a per pixel basis. A spread spectrum imaging system includes a transmitting module transmitting a transmitted optical signal that illuminates a target space and contains a transmitted pulse that is modulated with a first pseudo-noise (PN) code. The imaging system includes a receiving module that receives a reflected optical signal from an object. The reflected signal is processed by an optical array that detects a detected signal from the reflected optical signal, where the detected signal contains a plurality of pixels spanning a target space. When the determined PN code corresponds to the selected PN code, image information and the positional information is presented for the object. When different positional information is obtained for different pixels in the image, the imaging system may determine that different objects appear in the received image.
Owner:SCI APPL INT CORP
Method and apparatus for selectively applying interference cancellation in spread spectrum systems
ActiveUS20070183483A1High strengthIncrease signal strengthError preventionLine-faulsts/interference reductionSignal cancellationEngineering
The present invention is directed to the selective provision of interference canceled signal streams to demodulating fingers in a communication receiver. According to the present invention, potential interferer signal paths are identified. Signal streams having one or more potential interferer signals removed or canceled are created, and a correlation is performed to determine whether the strength of a desired signal path increased as a result. If the correlation indicates that the strength of a desired signal path was increased by the signal cancellation, the interference canceled signal stream is provided to the demodulation finger assigned to track the desired signal path. If the correlation determines that the strength of the desired signal path did not increase as a result of performing interference cancellation, the raw or a different interference canceled signal stream is provided to the demodulation finger.
Owner:III HLDG 1
Method and apparatus for characterizing a signal path carrying an operational signal
InactiveUS7250772B2Cost-effective and accurateEasy to detectSpectral/fourier analysisError preventionComputer scienceSpread spectrum
A method of characterizing a signal path includes (i) generating a reference spread-spectrum signal; (ii) coupling the reference spread-spectrum signal into the signal path while the signal path is carrying an operational signal; (iii) receiving a reflected spread-spectrum signal from the signal path generated in response to the reference spread-spectrum signal; and (iv) correlating the reflected spread-spectrum signal with the reference spread-spectrum signal to produce a correlation result corresponding to a characteristic of the signal path.
Owner:UNIV OF UTAH RES FOUND
Digital watermark embedding and decoding using encryption keys
Digital watermarks are embedded and decoded from host media signals like images and audio using encryption keys. The encryption keys are used to encrypt different components of the digital watermark message. The encryption keys can be used to scramble the digital watermark and components of it in alternative ways, including scrambling the mapping of the message to the host signal and scrambling carrier signals used to encode the message. Spread spectrum, feature based, and quantization based embedding and decoding schemes may be used in various combinations in the watermark encoder and decoder. Portions of the digital watermark may be encrypted to provide private watermark data, while other portions may be un-encrypted to provide public watermark data.
Owner:DIGIMARC CORP
Code sequence generator in a CDMA modem
Owner:INTERDIGITAL TECH CORP
Method and apparatus for position sensing
InactiveUS20060166681A1Direction finders using radio wavesTransmission control/equalisingData signalCombined use
Embodiments of the present invention include one or more wireless transmitting devices and an array of receiver units for receiving wireless communications from the transmitting devices. The transmitter devices and receiver units can be arranged in one, two or three dimensional configurations. Signals are transmitted from the devices for identification and accurate location determination. Spread spectrum techniques can be used, such as DSSS, FHSS, THSS, and pseudo-noise (PN) coding schemes, or combinations thereof. The transmitting devices can generate one or a plurality of data signals that are orthogonal-code modulated, to be decoded by the receiver units and a processor associated therewith. A plurality of transmitter signals can be received, identified, located, and data demodulated substantially simultaneously using embodiments of the invention. The combined use of array processing methods and diversity schemes can be used to reduce the effects of signal multi-path and occlusion.
Owner:XYZ INTERACTIVE TECH
Method and system for a remote downlink transmitter for increasing the capacity and downlink capability of a multiple access interference limited spread-spectrum wireless network
InactiveUS7535867B1Increased cost-effectivenessIncrease speedError preventionFrequency-division multiplex detailsEffective solutionCellular architecture
The present invention relates to a system and method for extending the coverage area and communication capacity of a spread-spectrum based wireless network. The system comprises a unique dual-scale, asymmetrical cellular architecture for a wireless network, wherein the communication uplink is based on a macro-cellular system, and the communication downlink is based on a micro-cellular system. Through the user of remote downlink transmitters in the micro-cellular system, the present invention provides a cost effective solution for increasing communication capacity, extending coverage area, and providing high-speed communication downlink.
Owner:LEIDOS
Multimode communication system
ActiveUS7280810B2Expand coverageImprove performanceElectric signal transmission systemsImage analysisModem deviceCommunications system
Multimode, multi-function, multiple modulator-demodulator (modem) system containing a fingerprint sensor, detection, identification, authentication, and processing device for one or multiple fingerprint information to activate one or multiple modulators for signal transmission and generation of authentication information signals. A location information receiver and a processor device for processing and combining the location information and fingerprint information activated signals with one or more additional user generated signals. Processed, combined signals are provided for filtering and / or spread spectrum encoding and / or cross-correlating and connection to one or more modulators and transmitters.
Owner:FEHER KAMILO
Shared receive path for simultaneous received signals
A method and apparatus are disclosed for a wireless communication device to simultaneously receive at least two signals. Two receiver portions are provided in the wireless communication device. A first receiver portion is configured to receive a first communication signal. A second receiver portion is configured to receive a second communication signal. The two receiver portions are configured to convert the first and second communication signals to a common frequency band. The common frequency band may be an intermediate frequency band or baseband frequency band. The converted first and second communication signals are combined in the common frequency band using an adder or other signal combiner. The combined signal is processed in a single signal processor. The communication device is able to resolve each of the received signals when the first communication signal is a narrowband signal and the second communication signal is a wideband signal, such as a spread spectrum signal.
Owner:QUALCOMM INC
System and method for positioning in configured environments
ActiveUS7511662B2Easy to useSize moreDirection finders using radio wavesPosition fixationFrequency spectrumCdma signal
The present invention relates to a system and method for providing location determination in a configured environment in which Global Navigation Satellite System Signals may not be available. In this regard, local beacon systems generate spread spectrum CDMA signals that are received by spectral compression units that derive physically meaningful observations without a requirement for correlation of the intercepted energy by means of the known spreading codes. The invention can coexist with communication assets already in place, and the design allows for self calibration, which simplifies installation and usage. The invention has utility in applications in which GNSS signals are unavailable or limited, for example, in warehouse inventory management, in search and rescue operations and in asset tracking in indoor environments.
Owner:TELECOMM SYST INC
Multiple access frequency hopping network with interference anticipation
InactiveUS6920171B2Spreading over bandwidthSecret communicationMulti-frequency code systemsMessage queueRadio equipment
Spread spectrum packet-switching radio devices (22) are operated in two or more ad-hoc networks or pico-networks (19, 20, 21) that share frequency-hopping channel and time slots that may collide. The frequency hopping sequences (54) of two or more masters (25) are exchanged using identity codes, permitting the devices to anticipate collision time slots (52). Priorities are assigned to the simultaneously operating piconets (19, 20, 21) during collision slots (52), e.g., as a function of their message queue size or latency, or other factors. Lower priority devices may abstain from transmitting during predicted collision slots (52), and / or a higher priority device may employ enhanced transmission resources during those slots, such as higher error correction levels, or various combinations of abstinence and error correction may be applied. Collisions are avoided or the higher priority piconet (19, 20, 21) is made likely to prevail in a collision.
Owner:GOOGLE TECH HLDG LLC +1
System and method for monitoring remote devices with a dual-mode wireless communication protocol
ActiveUS8031650B2Electric signal transmission systemsNetwork traffic/resource managementWireless communication protocolTransceiver
The present invention is generally directed to systems and device for monitoring remote device with a wireless, dual-mode communication protocol. As such, a representative embodiment is a system for monitoring and controlling remote devices. The system includes a first- and a second remote device; and a first and a second wireless transceiver integrated with the respective remote devices. The wireless transceivers are configured to communicate with at least one of a spread-spectrum communication protocol and a fixed-frequency communication protocol.
Owner:STATSIGNAL IPC
Narrow-band interference rejecting spread spectrum radio system and method
InactiveUS6975673B1Decrease requiredReduced computing resourceFrequency-modulated carrier systemsCommunication jammingTime domainDigital signal processing
A spread spectrum receiver and method having narrow-band interference rejection of narrow-band jamming signals using digital signal processing frequency domain techniques. The method performed in the receiver includes transforming the received signal to a frequency domain signal and identifying narrow-band interference components in the frequency domain signal; suppressing the identified narrow-band interference components by excising the identified narrow-band interference components from the frequency domain signal to produce an interference excised signal in the frequency domain, and storing in a memory frequencies corresponding to the identified narrow-band interference components; synchronizing a receiver code to a transmitter code in the frequency domain using the interference excised signal; generating coefficients for a time domain filter that includes notches at the frequencies corresponding to the excised narrow-band interference components and that jointly despreads and rejects narrow-band interference from the excised frequencies; applying the coefficients generated in the preceding step to the time domain filter, and despreading and filtering in real time in the time domain the received signal using the applied coefficients.
Owner:SENSUS SPECTRUM LLC
Method for communicating in dual-modes
ActiveUS20050195768A1Multiple modulation transmitter/receiver arrangementsConnection managementTelecommunicationsDual mode
The present invention is generally directed to methods for communicating in a dual-mode communication protocol. A representative embodiment of the present invention comprises: enabling communication in a spread-spectrum communication protocol, comprising: receiving a first portion of a communication frame at a first frequency channel, wherein the first portion of the communication frame comprises a data channel index that indicates a second frequency channel for receiving a second portion of the communication frame; switching to the second frequency channel; and receiving the second portion of the communication frame at the second frequency channel.
Owner:SIPCO
Remote radio operating system, and remote operating apparatus, mobile relay station and radio mobile working machine
InactiveUS6778097B1Improve reliabilityShort working hoursElectric signal transmission systemsDigital data processing detailsMobile relayRemote control
The present invention relates to remote radio control technology, and a remote radio control system includes a radio movable working machine (1), a remote control apparatus (6A), and a movable repeater station (7). First bidirectional communication means (31, 71) having a high radio wave directionality and first automatic tracking means (32, 71A) are provided between the working machine (1) and the repeater station (7), and second bidirectional communication means (63, 76) having a high radio wave directionality, second automatic tracking means (63A, 76A), and emergency spread spectrum bidirectional communication means (64, 87) for enabling bidirectional communication between the remote control apparatus (6A) and the repeater station (7) when communication by the second bidirectional communication means (63, 76) is impossible are provided between the remote control apparatus (6A) and the repeater station (7). Consequently, even if communication between the working machine (1) and the movable repeater station (7) is disabled, each of the working machine (1) and the repeater station (7) is permitted to perform a minimum necessary operation, and any other person than those skilled in actual controlling operation of the working machine (1) can perform remote control easily.
Owner:CATEPILLAR SARL
Emergency location transceivers (ELT)
InactiveUS20070032220A1Improve the quality of lifeEliminate and reduce cable caused potentially harmful currentTelevision system detailsMultiple modulation transmitter/receiver arrangementsTransceiverEngineering
Emergency Location Transceivers (ELT) and communication transceivers (transmitters and receivers) for reception and demodulation of location finder signals, Global Positioning System (GPS) satellite signals and non GPS satellite location finder and other location finder signals. The received location finder signals are demodulated to location finder baseband signals. Baseband signal processors for processing single or a plurality of input signals for providing Orthogonal Frequency Division Multiplex (OFDM) baseband signals, filtered signals, cross-correlated shaped in-phase and quadrature-phase baseband signals and spread spectrum signals. Signal modulators for modulating the processed signals and for providing the modulated signals to the signal transmitter for transmission of the modulated signals. Emergency receiver systems for reception, demodulation and processing of the modulated transmitted signals. Certain emergency receiver embodiments, such as receivers of calls made to emergency call number 911 contain two or more receive antennas for reception and processing of the transmitted modulated signal. In certain embodiments emergency receiver systems have two or more receive antennas operated in a diversity mode, for reception and processing of the transmitted modulated signal.
Owner:FEHER KAMILO
Highly bandwidth-efficient communications
InactiveUS20060193373A1Reduce distractionsSimple calculationSpatial transmit diversityTransmission control/equalisingFrequency spectrumCarrier signal
A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment. Such systems are compatible with bandwidth-on-demand and higher-order modulation formats and use advanced adaptation algorithms. In a specific embodiment the spectral and spatial components of the adaptive weights are calculated in a unified operation based on the mathematical analogy between the spectral and spatial descriptions of the airlink.
Owner:CINGULAR WIRELESS II LLC
Cellular wireless internet access system using spread spectrum and internet protocol
InactiveUS6865169B1Reduce environmental impactOvercome lossMultiplex communicationNetwork topologiesTime-division multiplexingUser equipment
A cellular wireless internet access system which operates in the 2.5 to 2.68 GHz band and which must comply with complex government regulations on power levels, subscriber equipment and interference levels yet which provides high data rates to users and cell sizes of 1½ miles radius or more from base stations with subscriber equipment and antennas mounted indoors. Such base stations are mounted low and use spread-spectrum transmission to comply with interference rules with respect to adjacent license areas. An unidirectional tear-drop coverage pattern is used at multiple cells to further reduce interference when required. Time division duplex is used to allow the system to operate on any single channel of varying bandwidth within the 2.5 to 2.68 GHz band. Backhaul transmission from base stations to the Internet is provided using base station radio equipment, operating either on a different frequency in the band or on the same frequency using a time-division peer-to-peer technique. Different effective data-rates are provided by a prioritization tiering technique.
Owner:NVIDIA CORP
System for using rapid acquisition spreading codes for spread-spectrum communications
InactiveUS20050265430A1Increase profitEnergy efficient ICTRadio transmission for post communicationCode division multiple accessCarrier signal
A system for rapidly acquiring a spreading code, used in a code division multiple access (CDMA) system, comprises a generator for generating a first long code and a second long code, with each long code having a length of N chips. The first long code is different from the second long code. A transmitter transmits the first long code and the second long code at a first phase angle and at a second phase angle, respectively, on a carrier signal over a communications channel using radio waves. The first long code and the second long code may be transmitted at an in-phase (I) angle and at a quadrature-phase (Q) angle, respectively, on the carrier signal. From the communications channel, an I acquisition circuit and a Q acquisition circuit may acquire, in parallel, the first long code and the second long code from the I angle and the Q angle, respectively, of the carrier signal by searching, in parallel, N / 2 chips of the first long code and the second long code.
Owner:INTERDIGITAL TECH CORP
Radio frequency motion tracking system and method
InactiveUS7009561B2Desirable effectReducing manual correlatingDirection finders using radio wavesCode conversionDouble differenceHandling system
A radio frequency (RF) motion capture system includes stationary sensor receivers, one or more transmitter marker tags on one or more objects to be tracked within a capture zone, at least one stationary reference tag transmitter, and a processing system for processing the received signals. The individual tags transmit burst of spread-spectrum RF signals. The transmitted signals include a common sync code, and a tag identification code that is unique to each tag. By computing double differences of pseudoranges, clock terms are cancelled out allowing the processing system to precisely determine the location of each tag as it moves through the capture zone without the need to synchronize clocks between sensors and tags. The system can be used for RF match moving.
Owner:MENACHE
Systems and methods for implementing S/SSTDR measurements
ActiveUS9244117B2Shorten the timeAccurate measurementResistance/reactance/impedenceElectronic circuit testingCircuit under testSpread spectrum
Systems and methods which utilize spread spectrum sensing on live circuits to obtain information regarding a circuit under test are provided. In some embodiments S / SSTDR testing may be utilized to obtain R, L, C and Z measurements from circuit components. In yet further embodiments, these measurements may be utilized to monitor the output of sensors on a circuit.
Owner:UNIV OF UTAH RES FOUND
Spread spectrum transceiver for use in wireless local area network and having multipath mitigation
InactiveUS6603801B1Good diversity selection metricGood energySpatial transmit diversityNetwork topologiesFinite impulse responseTransceiver
A method and spread spectrum transceiver for demodulating a spread spectrum signal is disclosed. A spread spectrum phase shift keyed (PSK) modulated information signal is received within a demodulator of a spread spectrum receiver on a signal channel. The information signal includes a sequence of data symbols formed from a plurality of high rate mode chips. A precursor portion of the signal channel is Viterbi detected. A multi-state trellis is formed having a predetermined number of states. A post-cursor portion of the signal channel is feedback equalized with a finite impulse response filter having feedback taps operatively connected to a chip detection circuit that tracks high rate mode chips and a carrier loop circuit for phase and frequency tracking. The information signal is despread within a spread spectrum code function correlator.
Owner:INTELLECTUAL VENTURES I LLC +1
Systems and methods for communicating spread spectrum signals using variable signal constellations
InactiveUS6934317B1Increase capacityMaximize capacityTransmitter specific arrangementsChannel coding adaptationComputer hardwareCommunications system
According to embodiments of the invention, a communications system includes an error correction encoder that error correction encodes a bitstream according to an error correction code. The system also includes a variable symbol generator that generates a symbol according to a selected one of a plurality of selectable signal constellations from a group of bits of the error correction encoded bitstream. The system further includes a spreader that spreads the symbol according to a spreading code, and a transmitter that transmits the spread symbol in a communications medium. Preferably, the plurality of selectable signal constellations includes at least two signal constellations of different order. In other embodiments, the error correction encoder includes a variable error-correction encoder that encodes the bitstream according to a selected error correction code of a plurality of selectable error correction codes. In still other embodiments, the spreader includes a variable spreader that spreads the symbol according to a selected spreading code of a plurality of selectable orthogonal spreading codes including at least two spreading codes of different lengths. A controller may select the error correction code used by the variable error correction encoder, the signal constellation used by the variable symbol generator, and the spreading code used by the variable spreader to provide a desired information transmission rate for the bitstream. Related methods are also described.
Owner:ERICSSON INC
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