Abstract: A roulette table, including an electronic system having at least one electronic circuit, a number of M antennas, a Code Division Multiple Access (CDMA) transmitter for sending a number of M orthogonal code sequences via the antennas, and a contactless communication interface for receiving the position from an electronic memory of the electronic circuit, in which the antennas are arranged below stake fields of the roulette table, and having chips, in which each chip is equipped with an electronic circuit.

Abstract: There is provided a video signal processing method for performing predetermined signal processing on an input video signal to transmit an output video signal in a form of a specified transmission format through a video signal line including invalid bit polarity setting processing to be performed by an invalid bit polarity setting unit, wherein, when there exists an invalid bit having no data corresponding to data making up the input video signal in the specified transmission format of the output video signal, to count the number of low and high levels of gray-level data of the input video signal to compare a numerical size between the number of low levels and the number of high levels for judgment and to set a polarity of the invalid bit based on the judgment result.

Abstract: Provided are a method and apparatus (receiver) of receiving and processing a radio signal in a transmitter-receiver environment. The radio signals are transmitted across a wireless interface using Ultra Wideband (UWB) pulses. A transmitted reference approach is utilized. The radio signal include pairs of UWB pulses with each pair of pulses separated by a fixed time delay. The two pulses are then combined to provide for improved noise immunity.

Abstract: A transmitting interconnect interface inserts clock mismatch compensation symbols into a transmitted data stream so as to allow the receiving interconnect interface to compensate for clock frequency mismatch between transmit-side and receive-side clocks. The transmitting interconnect interface adjusts the rate of insertion of these symbols based on a determination of the clock frequency mismatch. The transmitting interconnect interface can incrementally adjust the insertion rate to change substantially proportionally with changes in the clock frequency mismatch. Alternatively, the transmitting interconnect interface can set the insertion rate to one of two levels. By adapting the insertion rate to the current measured clock frequency mismatch, the bandwidth penalty incurred by transmitting clock mismatch compensation symbols in excess of that necessary to permit receiver clock tolerance compensation can be reduced, thereby permitting more transmit bandwidth to be used for transmitting data.

Abstract: To prevent a collision from occurring at the time of random access in cases such as handover, response to paging and the like where a mobile station apparatus performs random access in response to directions from a base station apparatus. In a mobile communication system in which a mobile station apparatus 200 uses a signature of a beforehand determined signature group at the time of random access with a base station apparatus 100, the signature group is comprised of a signature group managed by the base station apparatus 100 and another signature group managed by the mobile station apparatus 200. The signature group managed by the base station apparatus 100 includes signatures associated with particular random access reasons to be selected by the base station apparatus 100.

Abstract: A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band.

Abstract: A technology for modulating and demodulating a burst signal in a return link of a satellite system, in which the burst signal is modulated and transmitted from a transmission end of the return link and a symbol of the burst signal is identified and demodulated at a receiving end. The method includes estimating symbol timing of a burst received through the return link and synchronizing the estimated symbol timing of the burst to reference symbol timing; synchronizing a location of the timing-synchronized burst having the symbol timing synchronized to a location of a reference burst using a preamble symbol and a post-amble symbol of the timing-synchronized burst; and recovering a carrier of the location-synchronized burst whose location has been synchronized to the location of the reference burst using a pilot symbol of the location-synchronized burst.

Abstract: System and method for enabling the cohabitation of licensed and unlicensed communications devices. A method comprises at a receiver, receiving transmitted data, demodulating the transmitted data to produce spread symbols, despreading the spread symbols to produce received data, wherein the despreading comprises using an orthogonal sequence selected from a list of orthogonal sequences for use by all transmissions in the wireless network, and processing the received data.

Abstract: A synchronization method for impulse system ultra-wideband takes frame as basic unit for data transmission, each frame is divided into a preamble symbol part and a data part, wherein the preamble symbol part sends a known impulse sequence for channel estimation and synchronization; the data part takes the information to be transmitted; the preamble symbol part is divided into two parts of a positive and negative impulse sequence, which includes odd impulses with alternant positive and negative polarities, and a same direction impulse sequence, which is composed of impulses with same polarity and is the same as the polarity of the last impulse in the positive and negative impulse sequence. The method provides such advantages as high synchronization precision, small storage space, and capability of immediately finding out the synchronization position etc., and provides an important value for the development of the impulse system ultra-wideband wireless communication technique.

Abstract: A wireless communication system. The system comprises transmitter circuitry (BST1), the transmitter circuitry comprising encoder circuitry (50) for transmitting a plurality of frames (FR). Each of the plurality of frames comprises a primary synchronization code (PCS) and a second synchronization code (SSC). The encoder circuitry comprises of circuitry (501) for providing the primary synchronization code in response to a first sequence (32). The encoder circuitry further comprises circuitry (502) for providing the secondary synchronization code in response to a second sequence (54) and a third sequence (56). The second sequence is selected from a plurality of sequences. Each of the plurality of sequences is orthogonal with respect to all other sequences. The third sequence is a subset of bits from the first sequence.

Abstract: A method can include receiving, at a transmitter, during a symbol time that comprises a plurality of chip times, a data value for each of a plurality of distinct data channel inputs. During each chip time, the method can include (a) indexing a different row of a matrix of data bits; (b) decoding one channel input using a first subset of one or more columns of the indexed row; (c) determining a code value for the decoded one channel from a second subset of one or more columns of the indexed row; and (d) providing the coded data value to a transmission circuit for transmission to a receiver. Actions (a) to (d) can be performed for each of the plurality of chip times in the symbol time. In some implementations, the matrix of data bits is a Hadamard matrix with randomly shuffled rows.

Abstract: A detector receives detects a first known signal in a packet signal. An LTF correlation unit performs correlation processing on the packet signal received by a receiving unit. Upon detecting the arrival timing, an update correlation unit terminates a first window and performs correlation processing on the packet signal received by the receiving unit, in a second window. When correction timing is detected and when correction timing is more likely to be accurate than the arrival timing, an estimation unit changes the correction timing to the arrival timing; when the arrival timing is more likely to be accurate than the correction timing, the estimation unit maintains the arrival timing.

Abstract: A mobile electronic device that includes a circuitry configured to acquire synchronization with a spreading code of an intermediate frequency signal that is obtained by converting a frequency of a received signal from a satellite in a global positioning system into a predetermined intermediate frequency, demodulate a message included in the intermediate frequency signal, output a primary signal to a predetermined signal line, and attach a predetermined header to a secondary signal and output the result to the predetermined signal line, and includes a display unit configured to display data corresponding to the primary signal and the secondary signal, such that the primary signal includes results of measuring one of position, velocity, and time of the mobile electronic device based on the message that is demodulated by the circuitry, and that the secondary signal includes the intermediate frequency signal.

Abstract: Varying insertion rates of deletable characters that are discarded by a receiver, as a function of transmission rate in spread spectrum clocking systems. Such systems can generate a spread spectrum modulation, based on their knowledge about the rate of transmission. The systems can dynamically adjust the rate/numbers of deletable characters that are inserted in the transmission. Accordingly, the insertion rate can increase (or decrease) when the transmission rate exceeds above (or falls below) a predetermined threshold.

Abstract: The present invention relates to an apparatus and method for estimating a channel in a MIMO wireless telecommunication system supporting the 0FDM/0FDMA. The present invention, in estimating a channel by using two or more pilots included in at least one received signal among received signals of a first channel and a second channel received through a first receiving antenna and received signals of a third channel and a fourth channel received through a second receiving antenna, determines a subchannel mapping rule respectively for the received signals of the first channel to the fourth channel, and estimates a channel with a different method according to the determined subchannel mapping rule.

Abstract: A correlation calculating method of correlating a received code signal obtained by demodulating a received signal, which is a signal obtained by receiving a positioning satellite signal, with a replica code signal is provided which includes: correlating values of the replica code signal in a chip period with values of the received code signal at first to n-th arrival times obtained by varying an arrival time of the chip period by 1/n chip (where n is an integer equal to or greater than 2); and acquiring a correlation calculation result at a 1/n chip interval by synthesizing the correlation calculation results.

Abstract: Systems and methods for temperature-calibration of an uncompensated XO in a mobile device during mobile device operation. The XO is temperature-calibrated based on assistance from wireless signals, such as from satellite source, and optionally from terrestrial sources such as WWAN, CDMA, etc. Based on one or more received wireless signals received at a receiver, corresponding frequency estimates of the XO are obtained and correlated with corresponding operating temperatures in a processor. Based on one or more samples of frequency estimates and associated temperatures, the XO is temperature-calibrated in the processor wherein a frequency-temperature (FT) model is formulated for the XO. The frequency of the temperature-calibrated XO can be determined from the FT model at any given temperature.

Abstract: A method for operating an integrated transceiver, comprising coupling an operating transmitter and an operating receiver within the integrated wideband receiver, inputting a signal into the operating transmitter, performing a first conversion of the signal, wherein the signal is converted into a second signal, transmitting the second signal into the operating receiver, performing a second conversion of the signal, wherein the signal is converted into a third signal, transmitting the third signal into the operating transmitter, and adjusting the operating transmitter.

Abstract: A signal acquisition system efficiently acquires a transmitted signal even at very low power. The system may synchronize to a preamble structure in the transmitted signal and, for example, determine timing parameters that locate the preamble with respect to system timing or other clock references. The system is particularly effective at acquiring weak power signals and is also robust against significant noise and other impairments, and therefore improves the ability of a receiving device that incorporates the signal acquisition system to acquire the signal and establish communication with other devices.

Abstract: Sub-microsecond time transfer in a GPS/GNSS receiver using a weak GPS/GNSS signal is provided. The digitized complex baseband signal and the generated PN code are cross-correlated for each code period so as to output a complex correlation value at each code epoch of the generated PN code, where a sequence of the output correlation values form a data stream representing the navigation message. Bit synchronization generates bit sync pulses at bit boundaries. The location of a target segment having a known sequence at a known bit location in the navigation message is detected by searching through a plurality of subframes and accumulating search results for the plurality of subframes. Transmission time of the target segment is determined from the detected location of the target segment, with a certain time ambiguity. Accurate local time is determined by solving the time ambiguity using approximate time obtained from an external source.

Abstract: A communications network and method thereof include a base station controller configured to provide a repetition period of a primary synchronization channel to be equal to a predetermined integer value times a scrambling code length of the scrambling code of a common pilot channel. A user equipment in the network is configured to search for a known sequence comprising the primary synchronization channel to select a cell and a corresponding sub-frame/symbol timing from the selected cell.

Abstract: The invention includes a method for transmitting and detecting high speed Ultra Wideband pulses across a wireless interface. The transmitter includes a serializer and pulse generator. The receiver comprises a fixed delay line, multiplier, local serializer (with a sequence matching the transmitter), digital delay lines, low noise amplifier and logic fan-out buffer along with an array of D flip-flop pairs. Each flip-flop pair is enabled, at fixed time increments, to detect signals at a precise time; the timing is controlled by the pseudo-random sequence generated by the local serializer. A local tunable oscillator is controlled by detecting the phase change of the incoming signal and applying compensation to maintain the phase alignment and clock synchronization of the receiver to the clock reference of the transmitter. The invention uses a pair of pulses with a fixed delay and then relies on mixing the two to provide better noise immunity.

Abstract: Methods, systems, and apparatuses, including computer programs encoded on computer-readable media, are configured for receiving monitor data from a fault circuit indicator. A data stream is created based upon the monitor data. The data stream is spread with a common pseudo-noise (PN) code that is used by a plurality of nodes in communication with an access point. The spread data stream is transmitted at a first time based on a slot start time and a first randomly selected timing offset. The spread data stream is transmitted while at least a portion of a second spread data stream is transmitted at a second time based on the slot start time and a second randomly selected timing offset. The second spread data stream is spread with the common PN code.

Abstract: Methods and apparatus for solving problems caused by backoff procedures like that specified in the BLUETOOTH Link Layer Specification, by introducing selected randomizations of communication channels used for communication by scanning devices.

Abstract: Methods, systems, and apparatuses, including computer programs encoded on computer-readable media, are configured for receiving monitor data from a smart transformer. A data stream is created based upon the monitor data. The data stream is spread with a common pseudo-noise (PN) code that is used by a plurality of nodes in communication with an access point. The spread data stream is transmitted at a first time based on a slot start time and a first randomly selected timing offset. The spread data stream is transmitted while at least a portion of a second spread data stream is transmitted at a second time based on the slot start time and a second randomly selected timing offset. The second spread data stream is spread with the common PN code.

Abstract: A time division duplex (TDD) base station having a code group out of N code groups includes circuitry configured to transmit a primary synchronization code along with a plurality of secondary synchronization codes. The plurality of synchronization codes are quadrature phase shift keying modulated and number less than (log2 N)+1. The plurality of synchronization codes are used to identify the code group of the TDD base station.

Abstract: Automated PilotPN code conflict resolution using an access point with the assistance of one or more access terminals is disclosed. An exemplary method includes determining a set of access points, as well as determining a set of PilotPN codes used by the set of access points. Detection is then made concerning whether at least two access points of the set of access points have conflicting PilotPN codes. A first PilotPN code is allocated to one of the at least two access points having conflicting PilotPN codes. Additionally, one or more other PilotPN codes, which are distinct from the first PilotPN code, are allocating to remaining access points of the at least two access points having conflicting PilotPN codes. Corresponding apparatus and other exemplary methods are also disclosed.

Abstract: A method for performing delay locked looping upon a received signal which reduces the asymmetry of auto-correlation function resulting from sampling is provided. The received signal is a spread spectrum code signal, and the method includes: generating a plurality of replica spread spectrum code signals according to an estimated code phase delay and phase spacing, the replica spread spectrum code signals having phases respectively different from the phase of the received signal; calculating a spread spectrum code error statistics signal according to the replica spread spectrum code signals and the received signal; and adjusting the estimated code phase delay according to the spread spectrum code error statistics signal and a phase difference between a sampled point of at least one replica spread spectrum code signal and a corresponding signal transition point.

Abstract: Various embodiments are disclosed for providing timing tracking loops in a communication system. A communication system includes a delay locked loop (DLL) comprising a maximum region detector configured to identify a target channel profile comprising at least a portion of the multipath signals based on the timing information, the maximum region detector further configured to apply a weight vector to each channel tap in the target channel profile and determine a tap with a maximum power level relative to remaining channel taps in the channel profile. The system further comprises a window timing loop (WTL) adjuster configured to track a position of a channel estimation window (CEW) within an observation window corresponding to the maximum channel energy level, where the maximum channel energy level corresponds to the sum of the energy of all the taps for a given window.

Abstract: The present invention discloses a method for joint secondary synchronization signal detection and frame timing synchronization, including: (1) generating local secondary synchronization sequences SSC1—n and SSC2—n according to a sector number of a cell group; (2) converting a received time domain signal to a frequency domain signal to obtain secondary synchronization signals S1 and S2 to be detected; (3) performing inner product operation to obtain P1—n=P1—n?1+[S1,SSC1—n]+[S2,SSC2—n], and P2—n=P2—n?1+[S1,SSC2—n]+[S2,SSC1—n]; (4) selecting the maximum value P of absolute values of correlation values in the P1—n and P2—n, and judging whether the maximum value P is greater than a preset threshold Tmax, (5) if yes, taking the index of the maximum value P as an ID number of the cell group, or else, further carrying out step (2), and then further carrying out step (3).

Abstract: A method for communicating comprises generating at least one spreading code from a preferred Golay generator and/or a preferred generalized Golay generator. The preferred generalized Golay generator may comprise a plurality of preferred Golay generators. The outputs of the preferred Golay generator are logic 0 and 1. Each stage of the preferred Golay generator may comprise a single basic storage unit, such as a Flip-Flop. Generalized Golay codes comprise pseudo-complementary sequences having code lengths that differ from Golay complementary sequences and are characterized by low autocorrelation sidelobes relative to the autocorrelation peak.

Abstract: In described embodiments, data streams with irregular patterns are processed by transformations defined by recursively changing processor state, or iteration level. The data transformations are applied to an arbitrary long portion of data, instead of small portions, that are defined directly by a current processor state. Embodiments combine small parts of, for example, puncturing/repetition patterns into a pattern of bigger parts and apply these patterns of bigger parts to relatively large portions of input data.

Abstract: A power-consumption monitoring device, for taking measurements of the power consumed by an appliance. The device is connectable to a mains electrical circuit and operable to transmit the measurements to a master device through the circuit. Also presented is a master device, for receiving over a mains electrical circuit power-measurements transmitted by one or more power-consumption monitoring devices. Also presented is a power-line communications network comprising: a master device; and one or more power-consumption monitoring devices.

Abstract: Apparatus for locating a specific point in a received signal of cyclical nature, the apparatus comprising correlating means (16) for correlating the received signal with a code that is potentially present in the received signal, processing means (20,22,18) for multiplying the correlation result with a time-offset, complex-conjugated version of itself and filtering means (24,26,28) for low pass filtering the multiplication result to produce a signal suited to analysis for determination of said point and estimation of the frequency error.

Abstract: Noise measurements are made within a fraction of a single symbol period of a longest orthogonal code symbol. A control processor identifies an unoccupied code having a spreading factor that is less than a longest spreading factor for the system. A despreader measures symbol energy based on the unoccupied code and a noise estimator generates noise estimations based on the measured symbol energies. The subscriber station uses similar techniques in order to perform channel estimations within a period that is a fraction of a symbol period of a longest-spreading-factor code.

Abstract: A radio transmission device and a radio communication method employ sequence length decision units which hold a correspondence in which one basic sequence length is set for a plurality of transmission bandwidths. The sequence length decision units acquire transmission bandwidth information and decide a sequence length corresponding to the acquired transmission bandwidth information. A decision is made as to which of the cyclic extension process or the truncation process is to be executed on a Zadoff-Chu sequence according to the sizes of the acquired transmission bandwidth information and the basic sequence length. Then, a difference between the transmission bandwidth and the basic sequence length, i.e., the number of possible cyclic extension/truncation symbols, is obtained.

Abstract: A method of processing first and second corresponding signals having a delay therebetween. The method includes introducing a plurality of different delays between the first and second signals, successive delay amounts differing from each other by less than the interval between chip boundaries, and for each introduced delay, summing samples of the second signal which are obtained at the times of, at least, chip boundaries between bits of the first signal which have the same state, to obtain a value; thereby to obtain a representation of how the value varies according to the introduced delay, which representation contains a level change associated with an introduced delay which bears a predetermined relationship to the delay between the first and second signals.

Abstract: The present invention includes a method of determining a phase estimate for an input signal having pilot symbols. The method includes receiving a plurality of pilot symbols, and then multiplying two or more pilot symbol slots by corresponding correlator coefficients to correct a phase estimate of the input signal.

Abstract: To provide a clock control circuit, a demodulation device, and a spread spectrum method, which can reduce interference caused by a clock signal on which spread spectrum is performed when demodulating a signal. A clock controller 22 according to the present invention disperses a harmonic of a clock signal in a used frequency band of a reception signal and controls a harmonic remaining in the used frequency band after the dispersion. For example, the clock controller 22 controls an amplitude of the harmonic on the basis of a spread frequency used for the dispersion and a spread width of the harmonic.

Abstract: A method for operating an integrated transceiver, comprising coupling an operating transmitter and an operating receiver within the integrated wideband receiver, inputting a signal into the operating transmitter, performing a first conversion of the signal, wherein the signal is converted into a second signal, transmitting the second signal into the operating receiver, performing a second conversion of the signal, wherein the signal is converted into a third signal, transmitting the third signal into the operating transmitter, and adjusting the operating transmitter.

Abstract: A method of generating preamble sequence is disclosed. A channel used by a wireless device may be divided into four sub-channels, and the method includes forming a preamble sequence of a first sub-channel, making three replicas of the preamble sequence of the first sub-channel, each replica with a phase rotation of a first angle, a second angle, and a third angle respectively, for forming each preamble sequence of a second sub-channel, a third sub-channel, and a fourth sub-channel, and arranging the preamble sequences of the first, the second, the third, and the fourth sub-channels to form a preamble sequence of the channel.

Abstract: A method used in a wireless communication apparatus based on reference signals is provided. The method may include obtaining a plurality of pilot rules and obtaining radio channel information of a radio channel between the wireless communication apparatus and another wireless communication apparatus. The wireless communication apparatus may be in an area including at least one cell and using one or more data streams. Further, the method may include selecting applicable pilot rules from the plurality of pilot rules based on the radio channel information, creating at least one pilot structure to be used in the radio channel; and using the created at least one pilot structure to transmit data over the radio channel.

Abstract: In a wireless communication system, a portable device transmits a first signal spread based on a reference period indicated by a synchronization signal transmitted from an in-vehicle device and transmits a second signal spread based on an operation by a user. The in-vehicle device sets a search period based on a variation range in a delay time from when the synchronization signal is transmitted to when the spread first signal is transmitted and sets a residual period that starts at an ending point of the search period and ends at an ending point of the reference period when a starting point of the reference period is set at a starting point of the search period. When the in-vehicle device fails in a synchronous acquisition for the search period, the in-vehicle device performs a synchronous acquisition process for the residual period.

Abstract: A method for encrypting an information carrier comprising generating a sequence of data using a sequence generator, modulating, using a first modulator an output from the sequence generator such that an interference signal results, encoding the interference generator's synchronization information using an encoder, modulating, using a second modulator, the encoded synchronization information such that a synchronization carrier signal results, spreading the synchronization carrier signal using a spreader such that a spread sub-carrier synchronization signal results, and combining the modulated information carrier signal, interference signal, and spread sub-carrier synchronization signal using a signal combiner such that a composite signal results, the interference signal having one or more signal characteristics that results in obfuscation of the information carrier signal when the information carrier signal and interference signal are combined.

Abstract: Physical layer structures and related access schemes for unsynchronized communication networks are provided. Access channel information, preferably including a common synchronization code associated with all transceiver stations in a communication network and a cell-specific synchronization code uniquely associated with one of the transceiver stations, is modulated onto at least one set of time-continuous signal components of a communication signal. In order to access the communication network, communication terminals search for the access channel information in one or more sets of time-continuous signal components and synchronization parameters are then determined based on a location of the access channel information in the sets of time-continuous signal components. Some embodiments of the invention provide for joint frame synchronization and coarse timing synchronization.

Abstract: Examples are disclosed for transmitting and receiving schemes for multiuser single-carrier space time spreading (STS) with frequency domain equalization.

Abstract: Provided is a radio communication device which can suppress inter-code interference between an ACK/NACK signal and a CQI signal which are code-multiplexed. A diffusion unit (214) diffuses the ACK/NACK signal inputted from a judgment unit (208) by using a ZC sequence. A diffusion unit (219) diffuses the CQI signal by using a cyclic shift ZC sequence. By using a Walsh sequence, a diffusion unit (216) further diffuses the ACK/NACK signal which has been diffused by using the ZC sequence. A control unit (209) controls the diffusion unit (214), the diffusion unit (216), and the diffusion unit (219) so that the minimum value of the difference between the CQI signals from a plurality of mobile stations and a cyclic shift amount of the ACK/NACK signal is not smaller than the minimum value of the difference between the cyclic shift amounts of the ACK/NACK signals from the plurality of mobile stations.

Abstract: A human body communication system is provided. The human body communication system includes a transmitter and a receiver. The transmitter transmits a frame including a preamble, which is a Manchester-encoded pseudo noise (PN) code, to the human body. The receiver receives the frame from the human body, performs Manchester-decoding on the frame, performs cross-correlation on the decoding result and the PN code, and performs frame synchronization using the cross-correlation result. Accordingly, clock and data recovery performance is improved. Efficient frame synchronization with reduced computation amount can be provided.

Abstract: Provided is a system and method for terrestrial digital broadcasting service using a single frequency network without additional equipment. The system and method synchronizes input signals into transmitting stations by inserting a transmission synchronization signal into a header of TS periodically, and solves the problematic ambiguity of the trellis encoder by including a trellis encoder switching unit separately and initializing a memory of the trellis encoder. The terrestrial digital broadcasting system includes: a broadcasting station for multiplexing video, voice and additional signals into transport stream (TS) and transmitting the TS to the transmitting stations and a transmitting stations for receiving the TS and broadcast the TS to receiving stations through a single frequency network.

Abstract: A waveform-adaptive ultra-wideband (UWB) transmitter and noise-tracking UWB receiver for use in communications, object detection and radar applications. In one embodiment, the output of an oscillator is gated by a low-level impulse generator either directly or through an optional filter. In a special case of that embodiment wherein the oscillator is zero frequency and outputs a DC bias, a low-level impulse generator impulse-excites a bandpass filter to produce an UWB signal having an adjustable center frequency and desired bandwidth based on a characteristic of the filter. In another embodiment, the low-level impulse signal is approximated by a time-gated continuous-wave oscillator to produce an extremely wide bandwidth pulse with deterministic center frequency and bandwidth characteristics. The low-level impulse signal can be generated digitally. The UWB signal may be modulated to carry data, or may be used in object detection or ranging applications.