167results about "Modulated carrier system with wavelets" patented technology

Techniques for reducing peak-to-average power in multicarrier transmitters employ peak cancellation with subcarriers that are impaired by existing channel conditions. The use of Carrier Interferometry (CI) coding further improves the effectiveness of peak reduction. CI coding can also be impressed onto pulse sequences in the time domain, which enhances spectral selection and facilitates peak-power control.

The present invention provides for a methods, system, and apparatus relating to data transmission. One method of the present invention includes representing data using at least one pulse based on a Gaussian wave form, sending the at least one pulse over an electrically conductive guided media, and recovering the data from the at least one pulse. The present invention can be used in conjunction with telephony applications, cable tv applications, and data bus applications.

Systems, apparatus, and methods for new generations of wireless systems, including multiple standard, interoperable Third-Generation (3G) and Second-Generation (2G), Spread Spectrum CDMA, WCDMA, GSM, Enhanced GSM systems and CSMA, TDMA and OFDM. Bit Rate Agile (BRA), Modulation and Code Selectable processing techniques of Gaussian Minimum Shift Keying (GMSK), Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), and of Mis-Matched demodulator filters in which the demodulator filter set is mismatched to the filter set of the signal modulator.

An orthogonal wavelet division multiplexing (OWDM) communication system including a synthesis section and a channel interface. The synthesis section includes a filter pair bank with multiple inputs and an output that provides an OWDM signal. Each input receives a corresponding symbol of a supersymbol, where the symbols are from a selected modulation scheme. The synthesis section generates the OWDM signal as a combination of weighted OWDM pulses, where each weighted OWDM pulse represents of a symbol of the supersymbol. An OWDM Spread Spectrum (OWSS) communication system that uses broad-time and broadband pulses generated from a family of OWDM pulses together with a set of orthogonal PN code vectors. The OWSS pulses are mutually orthogonal and allow multi-user operation. Each user is assigned an OWSS pulse corresponding to a particular PN code. OWSS enables high rate operation for wireless channels with the use of an equalizer with FE and DFE sections.

The present invention provides a system and method for transmitting an ultrawideband (UWB) signal that is composed of an orthogonal frequency-division multiplexing (OFDM) based signal that is transmitted in an underlay manner and an impulse radio based signal that is transmitted in an overlay manner. The system and method are effective in determining an interference temperature for each of multiple carriers within the UWB signal and classifying each one of the multiple carriers of the channel as being an interfered carrier or a non-interfered carrier based on the interference temperature for each one of multiple carriers. The desired signal is then transmitted on the interfered carriers at a signal power that is not greater than the power limit of the underlay UWB policy and on the non-interfered carriers at a signal power that is greater than the power limit of the underlay UWB policy.

A sinusoidal R.F. carrier is modulated for the transmission of digital binary datastreams through the deletion of carrier wavelets. These wavelets are defined between zero crossover positions representing zero energy locations. One or more wavelets are switched out of the carrier at the zero crossing positions to avoid sideband generation occasioned by electromagnetic energy disturbance. Transmissional amplification as well as receptional amplification is carried out with non-resonating amplifier architecture.

Method and process for receiving, demodulating, equalizing and processing of Modulation Demodulation Format Selectable (MFS) received signal, received from two or more than two antennas and from diversity receivers. Baseband processing filtering and adaptively equalizing demodulated signals and providing filtered equalized burst operated Time Division Multiplexed (TDM) cross-correlated in-phase and quadrature phase signal, spread spectrum Code Division Multiple Access (CDMA) signal and Orthogonal Frequency Division Multiplexed (OFDM) signals. Demodulation of peak limited cross-correlated OFDM signals. Demodulation and adaptive equalization of receive filtered signal, wherein the received filtered signal is mis-matched to transmit filtered signal. Process for receiving and demodulating MFS signals received from modulated linearly amplified and transmit filtered modulated non-linearly amplified (NLA) signal transmitters. Demodulation and processing of cross-correlated TDM, spread, spectrum and OFDM signals.

A system and method are provided for authenticating a new device in a wireless network using an authentication device. First, the new device estimates the distance between the new device and the authenticating device as a first distance measurement, and sends the first distance measurement to the authentication device. The authentication device then estimates the distance between the new device and the authenticating device as a second distance measurement. The authentication device then evaluates the first and second distance measurements to determine if they meet authentication criteria and sends authentication data to the new device only if the first and second distance measurements meet the authentication criteria. These criteria can be that they do not differ by more than a set error value or that they both are below a set maximum value.

A method and system for reception of electromagnetic waves in which interference with radio frequencies of other electronics devices occurs comprising;

• at least one transmitter for transmitting electromagnetic radiation at a wide range of frequencies;
• at least one receiver fix receiving the received signal comprising the first electromagnetic radiation and RF interfering signal data;
• a first memory portion for storing transmitted signal waveforms;
• a second memory portion for storing RF interfering signal data;
• a switch for periodically allowing the RF interfering signal data to enter the second memory portion from the receiver;
• the at least one processor operating to process and compare the received, signal containing RE signal data and first electromagnetic radiation by matching the received signal against data relating to the transmitted signal waveforms from the first memory portion and RF interfering signal data from the second memory portion, and extract the RF interfering signal data.

Spread Spectrum baseband signals, in-phase and quadrature-phase cross-correlated baseband signals and other filtered baseband signals connected to modulators for providing modulated signals. Modulator selection for modulated signal selection or for multiple modulated signals provided to one or more antennas for signal transmission.

A method, device and computer readable medium for enabling and blocking communications with a remote device based on a distance of the remote device. The method on which the device and computer readable medium are based includes transmitting a message from a local device to a remote device via an ultra wide band (UWB) wireless medium and receiving a response from the remote device via the UWB wireless medium. The transmitting and receiving steps are preferably performed in accordance with a Media Access Control (MAC) protocol. A distance between the local device and the remote device is then determined based on a time between the transmitting of the message and the receiving of the response and a function, such as communicating with the remote device, is performed in the local device based on the distance determined. The communication between the local device and the remote device may be enabled or disabled depending on the distance that the remote device is from the local device. In addition, the distance information for a remote device may be continually updated, or updated only if communication to the remote device are blocked. A positional map may be generated based on distance data determined for a plurality of reference points and the user may select the remote device from the positional map to enable communications to the positional map.

An ultra-wide band (UWB) waveform generator and encoder for use in a UWB digital communication system. The UWB waveform is made up of a sequence of shaped wavelets. The waveform generator produces multi-amplitude, multi-phase wavelets that are time-constrained, zero mean, and can be orthogonal in phase, yet still have a −10 dB power spectral bandwidth that is larger than the frequency of the peak of the power spectrum In one embodiment, the wavelets are bi-phase wavelets. The encoder multiplies each data bit by an n-bit identifying code, (e.g., a user code), resulting in a group of wavelets corresponding to each data bit. The identifying codeword is passed onto the UWB waveform generator for generation of a UWB waveform that can be transmitted via an antenna.

Spectrum-sensing algorithms and methods may be provided for use in cognitive radios and other applications. The spectrum-sensing algorithms and methods may include receiving an input spectrum having a plurality of channels, performing a coarse scan of the plurality of channels of the input spectrum to determine one or more occupied candidate channels and vacant candidate channels, where the coarse scan is associated with a first resolution bandwidth and a first frequency sweep increment, performing a fine scan of the occupied candidate channels and the vacant candidate channels to determine actually occupied channels and actually vacant channels, where the fine scan is associated with a second resolution bandwidth and a second frequency sweep increment, and storing an indication of the actually occupied channels and the actually vacant channels.

The present invention provides for a methods, system, and apparatus relating to data transmission. One method of the present invention includes representing data using at least one ultra wideband pulse, sending the at least one ultra wideband pulse over an electrically conductive guided media, and recovering the data from the at least one ultra wideband pulse. The present invention can be used in conjunction with telephony applications, cable TV applications, power line applications, fiber optic applications, and data bus applications.

Systems, methods, and apparatuses are provided for coarse-sensing modules that are operative for providing initial determinations of spectrum occupancy. The coarse-sensing modules may include a wavelet waveform generator providing a plurality of wavelet pulses, and a multiplier that combines the wavelet pulses with an input signal to form a correlation signal. The coarse sensing modules may further include an integrator that receives the generated correlation signal from the multiplier, where the integrator determines correlation values from integrating the correlation signal, and a spectrum recognition module in communication with the integrator that determines an available spectrum segment based at least in part on the correlation values. In addition, the spectrum recognition module may determine an available spectrum segment by utilizing information from a spectrum usage database, where the spectrum usage database includes information associated with one or more known signal types.