Abstract: A base station transmits a message to a plurality of wireless devices in connected mode. The message comprises a subframe allocation bitmap indicating a plurality of subframes. The plurality of subframes comprises a plurality of special subframes. During majority of symbols of a special subframe of a base station, no signal is transmitted by the base station or signals are transmitted at a special subframe power level that is different from a transmit power during a non-special subframe.

Abstract: In an ultra-wideband (“UWB”) receiver, a received UWB signal is periodically digitized as a series of ternary samples. The samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (“CIR”) are developed. When a start-of-frame delimiter (“SFD”) is detected, the best CIR estimate is provided to a channel matched filter (“CMF”) substantially to filter channel-injected noise.

Abstract: An integrated circuit for facilitating spread spectrum reception of data having a data bit period includes an hypothesis search circuit (120, 210, 220) operable to correlate a pseudorandom code with a signal input based on a received signal to produce correlation results, and a processor circuit (320) operable to coherently integrate the correlation results over plural sample windows (PreD1, PreD2) staggered relative to each other in the coherent integration interval and to non-coherently combine the coherently integrated results corresponding to the plural sample windows (PreD1, PreD2) to produce a received signal output, whereby enhancing performance. Other circuits, receivers and processes are also disclosed.

Abstract: The invention relates to a machine tool monitoring device. It is proposed that the machine tool monitoring device comprises at least one signal unit for an ultra wide band operation.

Abstract: Methods and apparatus are disclosed for receiving a diversity transmitted signal using a Rake or G-Rake receiver in a radio system. Signals are diversity transmitted in a first and second symbol period by two or more antennas. One or more receive antennas receive the diverse transmit signals. Weights are generated to account for the correlation between the channels over which the diverse transmit signals are transmitted in the first and second symbol period and are used to weight the received signals. The weighted signals are then fed to a mutual receiver.

Abstract: The present disclosure relates to the field of pulse compression in signal processing, and more particularly, to systems and methods for the synthesis of waveforms for suppressing sidelobes and sidebands using a combination of time and spectral control. More specifically, the present disclosure relates to a set of waveform symbols which can be used to maximize use of disaggregated grey-space spectrum, adapt to changing spectral condition, and maintain or enhance data rates relative to standard binary phase-shift keying (BPSK) under normal conditions.

Abstract: A method of reducing the glare of at least one receiver within a system, in particular a geolocation system, the system including: at least one first emitter emitting at least a first signal modulated by a first code, at least a second emitter emitting at least one second signal modulated by a second code, which is repetitive and potentially variable, and a third signal out of phase with respect to the second signal, the third signal being modulated by the second code delayed by a first delay, and the receiver, the latter being configured so as to detect signals emitted by the first and second emitters and implementing, for the tracking of the first signal, a local signal.

Abstract: In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for transmitting data over discontiguous portions of radio frequency spectrum. Data that is to be wirelessly transmitted to a remote computing device is received. A first signal that encodes the data across a band of radio frequencies is generated. The first signal is split into multiple signals, each of the multiple signals being associated with a different portion of the band of radio frequencies. Each of the multiple signals is filtered to isolate each respective one of the multiple signals to its associated portion of the band of radio frequencies. At least one of the multiple signals is frequency translated. Each of the multiple signals are combined after the filtering of each of the multiple signals. The second signal is provided for wireless transmission by an antenna.

Abstract: The present invention, pertaining to the field of mobile broadcast television technologies, discloses a method and apparatus for generating a broadcast positioning signal, and a positioning method. According to the present invention, a broadcast positioning signal is generated by inserting a spread spectrum signal and a first spread spectrum signal in an orthogonal frequency-division multiplexing (OFDM) signal, and a receiver is positioned according to broadcast positioning signals from at least three different senders.

Abstract: Embodiments herein relate to a method in a radio base station for transmitting information of an allocation of a radio resource allocated to a second user equipment. The radio base station is arranged to serve a first user equipment and the second user equipment in a cell of a radio communications network. The radio resource in the cell comprises Physical Resource Blocks that are organized in radio frames comprising subframes. The radio base station allocates a radio resource to the second user equipment in a subframe of the cell based on a frequency hopping scheme of the first user equipment. Also, the radio base station transmits a message to the second user equipment, which message indicates the allocated radio resource.

Abstract: A wireless spread-spectrum communication system for transmitting data includes a plurality of end point transmitters and at least one receiver. The end point transmitters transmit data via a frequency-hopped spread-spectrum signal where the transmitting signal is sent without the benefit of frequency stabilization. The receiver is responsive to the frequency-hopping spread-spectrum signals and includes a correlator and a signal processor. The correlator samples at least a first portion of a preamble of the signal and correlates the portion of the preamble with a known preamble pattern to determine a probability of correlation. The signal processor applies a Fast Fourier Transform algorithm to the signal in response to the probability of correlation to track a narrowband frequency of the signal based on at least a second portion of the preamble and to decode data encoded within the signal subsequent to the preamble.

Abstract: A communication apparatus and method for operating a communication apparatus are provided. The communication apparatus is configured to determine whether a sub-frequency band causing interference is present among sub-frequency bands included in a reception frequency band group, and to send to another communication apparatus an interference avoidance request signal which requests the other communication apparatus to transmit signals by use of remaining sub-frequency bands except the sub-frequency band causing interference, leading to simpler and more efficient interference avoidance.

Abstract: A transmitting apparatus for transmitting signals in a multi carrier system on the basis of a frame structure, each frame comprising at least two preamble patterns adjacent to each other in the frequency direction and at least two data patterns, said transmitting apparatus comprising a pilot mapper configured to map the same sequence of pilot signals on frequency carriers of each of said at least two preamble patterns in a frame, each preamble pattern having the same length, a data mapper configured to map data on frequency carriers of said at least two data patterns in a frame a transformer configured to transform said preamble patterns and said data patterns from the frequency domain into the time domain in order to generate a time domain transmission signal, and a transmitter configured transmit said transmission signal.

Abstract: In a multiple interface, low power and lossy network comprising a plurality of nodes, a low transmission power and medium transmission power topology are defined for the network and a channel-hopping schedule is defined for the devices operating in each topology. A sender determines that data is capable of being transmitted via a link on the low transmission power topology. The sender determines the transmission parameters for the transmission of the data over the link on the low transmission power topology and determines a low transmission power channel for transmission of the data. The sender transmits the determined channel and the transmission parameters to the receiver. The sender transmits the data via the determined channel in the low transmission power topology.

Abstract: A preamble of a frame for a multiple input multiple output (MIMO) wireless communication for a first transmit antenna of the MIMO communication includes a legacy preamble portion in accordance with a legacy wireless communication protocol. The preamble of the frame for the MIMO wireless communication for the first transmit antenna also includes a current protocol preamble portion in accordance with a protocol of the MIMO wireless communication. The preamble of a frame for at least a second antenna of the MIMO communication includes a cyclically shifted legacy preamble portion for the frame. The preamble of the frame for the MIMO wireless communication for the second transmit antenna also includes a second current protocol preamble portion in accordance with a protocol of the MIMO wireless communication.

Abstract: The present invention relates to a wireless communication system. More particularly, the present invention relates to a method for transmitting control information through a PUCCH in a wireless system and to a device therefore.

Abstract: Provided are a decoding apparatus and method for a system supporting an Orthogonal Frequency Division Multiple Access (OFDMA) scheme, the apparatus and method compensating received signals according to a wireless channel estimation result and thereby simply performing decoding by a coherent method. The decoding method includes the steps of: receiving a Quadrature phase shift keying (QPSK) modulated signal; compensating the received signals by applying a result of channel estimation based on pilot signals to the received signals; performing subcarrier demodulation to generate correlation metrics on the basis of the compensated received signals; and performing decoding using a decoding metric derived from the correlation metrics. The decoding apparatus and method compensate a received wireless signal according to a channel estimation result of a wireless channel through which a signal is transmitted, thereby performing decoding by a coherent method having a simple structure.

Abstract: Communications systems and/or methods are disclosed that may be used to convey information by forming, and then using, a plurality of frequency agile baseband waveforms, wherein any two different waveforms of the plurality of frequency agile baseband waveforms comprise an orthogonality therebetween. The systems/methods disclosed can convey information by mapping an information sequence into a baseband waveform sequence that includes waveforms of the plurality of baseband waveforms, and by transmitting the baseband waveform sequence. Such systems and/or methods can provide extreme privacy, cognitive radio capability, robustness to fading and interference, communications performance associated with M-ary orthonormal signaling and/or high multiple-access capacity.

Abstract: Provided is a radio communication device which can make Acknowledgement (ACK) reception quality and Negative Acknowledgement (NACK) reception quality to be equal to each other. The device includes: a scrambling unit (214) which multiplies a response signal after modulated, by a scrambling code “1” or “e?j(?/2)” so as to rotate a constellation for each of response signals on a cyclic shift axis; a spread unit (215) which performs a primary spread of the response signal by using a Zero Auto Correlation (ZAC) sequence set by a control unit (209); and a spread unit (218) which performs a secondary spread of the response signal after subjected to the primary spread, by using a block-wise spread code sequence set by the control unit (209).

Abstract: A transmission apparatus and method for transmitting signals in a multi carrier transmission system comprises a modulator, a band information generator that generates band information defining the frequency bands corresponding to all of the data streams carried within that frequency channel, said band information including a tuning frequency indicator indicating a tuning frequency and a tuning frequency type indicator indicating the type of tuning frequency indicated by said tuning frequency indicator, wherein said type is selected from a group comprising at least a first type indicating a tuning frequency of a frequency band and a second type indicating a center frequency of a frequency channel, and a transmitter.

Abstract: A mobile station receives system time information from a source base transceiver station (BTS) in a spread spectrum communication system. The mobile station estimates a distance between the mobile station and the source BTS. The mobile station calculates a propagation delay based on the estimated distance. The mobile station develops a propagation-delay-adjusted time reference based on the system time information and the calculated propagation delay. The mobile station uses the propagation-delay-adjusted time reference to search for a target pseudonoise (PN) offset corresponding to a target BTS in the spread spectrum communication system. The mobile station may be closer to the target BTS than the source BTS.

Abstract: System(s) and method(s) are provided to configure receivers in a mobile device to mitigate receiver overload and fully or nearly-fully utilize available spectrum for communication. Configuration is dictated at least in part by at least one of radio link quality or available receiver specifications, and it can be effected by the mobile device or a base station that serves the mobile device. Receiver configuration includes various spectrally asymmetric receivers that tune respective disparate portions of the available spectrum to maximize utilization thereof in the spectral regions prone to overload conditions. In severe overload conditions, a single receiver can be configured to operate in a frequency band spectrally adjacent to a sub-band that leads to overload conditions when employed for telecommunication.

Abstract: A method for estimating a scrambling code used on an uplink of a WCDMA system. The scrambling code is obtained from a Gold code, sum of a first specific M-sequence of the user and of a second M-sequence known from the receiver. After sampling of the signal received at the chip frequency of the scrambling code, the successive samples are subject to a differential treatment and the sequence of differential values is multiplied by the second M-sequence. The observables thereby obtained are decoded with the aid of a belief propagation iterative decoding. The decoded values then serve to determine the content of the shift register of the generator of the first M-sequence. One then deduces therefrom the Gold code and an estimation of the scrambling code, ?.

Abstract: The present invention discloses a method and a device for transmitting sounding reference signal in a multi-antenna system, wherein the method includes acquiring antenna grouping information, and grouping antennas according to the antenna grouping information; and transmitting SRS on the respective antennas, wherein different antenna groups transmit the SRS in different frequency bands at a same moment. With the present invention, the interference with a base station of an adjacent cell in a certain frequency band is enabled to be reduced.

Abstract: The present invention is a double-layer multi-carrier ultra-wideband wireless communication method, wherein the frequency band for ultra-wideband communication is divided into a plurality of sub-bands, then one or more sub-bands are used for data transmission, and the Orthogonal Frequency Division Multiplex (OFDM) multi-carrier transmission technology is used in each sub-band. In the transmitting party, the data symbols to be transmitted are allocated on M branches corresponding to the M sub-bands, and the OFDM modulation is implemented on the data symbols on each branch to obtain M branches of parallel data, then digital baseband multi-carrier modulation is implemented on the M branches of parallel data. Thereby, the spectrum of data on each branch is moved onto the digital sub-band corresponding to the radio sub-band one to one, so the digital baseband signal of the radio signal to be transmitted is obtained.

Abstract: A transmitting device and a receiving device wherein, on the transmitting side, a signal creation unit creates, as its output, a signal generated adding up the signals assuming that different data has passed through multiple virtual channels and, on the receiving side, oversampling is performed, the sampled data is distributed, and signals are detected assuming that the distributed data is the output of multiple virtual reception antennas.

Abstract: Common wave and sideband mitigation communication systems and methods are provided that can be used with both wireless and wired communication links. The systems and methods provided can enable faster data rates, greater immunity to noise, increased bandwidth/spectrum efficiency and/or other benefits. Applications include but are not limited to: cell phones, smartphones (e.g., iPhone, BlackBerry, etc.), wireless Internet, local area networks (e.g., WiFi type applications), wide area networks (e.g., WiMAX type applications), personal digital assistants, computers, Internet service providers and communications satellites.

Abstract: A method of delay spread compensation, suitable for use in a communication device a having plurality of receiver antennas, is disclosed. The method comprises receiving a plurality of signals, each via a respective antenna, wherein each signal comprises a signal component corresponding to a transmitted signal, and wherein each received signal experiences a respective channel impulse response having a corresponding delay spread; determining estimates of each of the channel impulse responses; calculating post-coding characteristics based on the estimates of the channel impulse responses; and post-coding the plurality of received signals using the post-coding characteristics to produce at least a first delay spread compensated signal. Corresponding computer program product, processing arrangement and communication device are also disclosed.

Abstract: The present invention proposes an LTE eNodeB receiver channel estimation technique that is referred to as reduced complexity minimum mean squared error (MMSE) technique for channel estimation. From the invention's assumptions, estimations and modified calculations, the present invention generates precise channel estimates of RS using the reduced complexity MMSE matrix and previously computed LS channel estimates HLS is as follows: (Formula I) which generates precise channel estimates of RS using the reduced complexity MMSE matrix and previously computed LS channel estimates. As a second aspect of the present invention, it is desired that the SNR be estimated within ?3 dB of the actual channel SNR. As a third aspect of the invention, an adaptive method of data channel interpolation from RS channel is being proposed in this invention.

Abstract: Systems, apparatuses and methods for managing message communications in systems employing frequency hopping. One method according to the invention involves transmitting a message via a frequency of a frequency hopping sequence, and determining when the same frequency will reoccur in the frequency hopping sequence. Relevant portions of the device enter a sleep mode, and the device emerges from the sleep mode when the frequency at which the message was transmitted reoccurs in the frequency hopping sequence. The device monitors for a response to the message via the frequency at which the message was transmitted when the frequency reoccurs in the frequency hopping sequence.

Abstract: The differential ultra-wideband indoor positioning method provides differential positioning to increase the accuracy of ultra-wideband (UWB) based indoor position estimation. Knowledge about common errors can be learned by employment of a reference source, where the difference between its known and estimated position (differential operation in solution domain), or the difference between the known and measured ranges (differential operation in measurement domain), provides invaluable information to be utilized in reducing errors in estimating the position of the target source. Differential operation accuracy reaches far beyond the accuracy of the non-differential setting.

Abstract: A transmission/reception installation for microwave radio signals, including a unit for transmission/reception including a receiver for receiving the electric signals from the conversion of radio signals received via a terrestrial or satellite link, referred to as forward-link signals, a demodulator for demodulating the electric signals using a first modulation/demodulation protocol, a modulator for modulating electric signals using a second modulation/demodulation protocol that is different than the first protocol, the second protocol being a spread-spectrum protocol, the modulator modulating the signals demodulated by the demodulator, and a converter for converting the electric signals modulated using a spread-spectrum protocol into radio signals that can be transmitted via a satellite link.

Abstract: A wireless device comprises a code-assignment module configured for assigning Golay codes to be used for spreading, a spreading module configured for spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data, and a transmitter configured for transmitting the signal. The wireless device may transmit a first beacon signal via a set of quasi-omni beam patterns, and a second beacon signal via a set directional beam patterns. The first beacon signal has a first transmission rate that is higher than the second beacon signal's transmission rate. Extended Golay codes having zero periodic cross-correlation may be generated from a Golay code and a set of short sequences. A data block transmitted by the wireless device may comprise Golay codes and data portions, wherein every data portion is between two Golay codes and every Golay code is between two data portions.

Abstract: Communication signal processing entails generating an overall signal correlation estimate that reflects overall impairment present in a received signal before despreading. Processing further includes parametrically constructing one or more component-specific correction terms as a function of one or more component signal correlation estimates, each estimate reflecting a particular component of the overall impairment. Combining weights are derived, as a function of this overall estimate and the correction term(s), so that they exclude the contribution of the impairment component(s) to the overall impairment. These weights are used to combine signal samples in an equalization process. As the combining weights exclude the contribution of the impairment component(s) to the overall impairment, the equalization process utilizing the weights exclusively suppresses impairment that is not attributable to the component(s).

Abstract: According to one embodiment, a wireless receiving apparatus includes a receiver, a phase rotation module and a demodulator. The receiver receives a first signal, the first signal being processed a bit conversion, a scramble and an M-phase shift keying modulation processes. The phase rotation module multiplies a first symbol obtained from the first signal with an amount of phase rotation determined by a scramble sequence used for the scramble, to obtain a second symbol. The demodulator demodulates the second symbol by referring to signal points of N-PSK replica signal generated based on a data rate and the bit conversion process and calculates a likelihood obtained from demodulation as a soft decision value.

Abstract: Methods and User Equipment (UE) apparatuses are provided for transmitting Reference Signals (RSs). A method includes receiving a cell-specific sequence-hopping parameter; receiving a UE-specific sequence-hopping parameter; determining a reference signal sequence based on the UE-specific sequence-hopping parameter; and transmitting the reference signal based on the determined reference signal sequence. Sequence hopping does not apply to the reference signal sequence if the cell-specific sequence-hopping parameter indicates that the sequence hopping is enabled and the UE-specific sequence-hopping parameter indicates that the sequence hopping is disabled.

Abstract: A device includes a delay profile estimator to estimate a delay profile of multiple paths of a radio signal, wherein the delay profile indicates signal powers of the multiple paths as a function of time delay. The device further includes a path selector to select a path from the delay profile if the path has a signal power higher than a threshold. The threshold has a first threshold value in a first section of the delay profile which is higher than a second threshold value in a second section of the delay profile.

Abstract: The present invention discloses a method and a device for detecting a primary synchronization signal and generating a sequence in a LTE system, so as to solve the problem that the overhead for 3GPP LTE system to store a local primary synchronization sequence is too much during the initial cell search process. The method for detecting a primary synchronization signal includes: directly generating a local primary synchronization signal sequence with equal amplitude in the time domain as a matched filter; performing a front-end processing for a received signal; performing the matched filtering between the received signal after the front-end processing and the local primary synchronization signal sequence; judging the output amplitude of the signal sequence obtained after the matched filtering; and then obtaining a judgment result of the local primary synchronization signal sequence.

Abstract: A method implemented in a multiple-antenna transceiver includes adapting a plurality of sets of rake coefficients based on a plurality of signals received via a plurality of single-input, multiple-output (SIMO) channels. Each signal of the plurality of signals corresponds to a single signal transmitted by a remote transceiver, and each set of the adapted sets of rake coefficients corresponds to an estimate of a respective one of the plurality of SIMO channels. The method also includes selecting, according to at least one selection criterion, one coefficient from each set of the plurality of sets of rake coefficients, generating a transmit steering vector based on the selected coefficients, and applying the transmit steering vector to a signal to be transmitted to the remote transceiver.

Abstract: A user equipment (UE) with circuitry configured to determine a pathloss associated with a received signal. The circuitry is configured to receive an adjustment and adjust a value in response to the received adjustment. The circuitry is configured to determine a transmit power level based on multiplying the determined pathloss by a parameter and adding the adjusted value to a result of the multiplying, wherein the parameter is value in the range of 0 to 1. The circuitry is configured to transmit a signal at the determined transmit power level.

Abstract: A frequency-agile radio receiver controlled by a radio controller hops through a plurality of radio frequencies where discrete frequency-hopping spread spectrum digital transmissions may exist, where the transmitter's hopping sequence is not known, and where it is not necessary to receive every transmission of interest. The controller accumulates counters of the number of transmissions of interest it receives at each of a plurality of frequencies. It then creates a new frequency-hopping sequence consisting primarily of those frequencies whose received transmission counts exceed a certain threshold. The controller continues to tune the receiver in a hopping pattern, allocating more of the receiver's time to those frequencies where more transmissions have been received in the past. Doing so improves the likelihood that transmissions of interest will be received in the future.

Abstract: Implementation and operation of a multiple protocol receiver are described herein. In one example, a multiple protocol receiver in a node may alternate between first and second states. In a first state, the multiple protocol receiver listens simultaneously for a plurality of differently modulated signals. Such listening may be performed in a parallel manner, wherein a plurality of preamble detection processes each listens for a specific preamble. The listening may result in detection of a preamble of a packet, which triggers transition to the second state. The detected preamble may indicate a protocol used in transmission of the packet. The received packet may then be demodulated according to, for example, a data rate, synchronization, redundancy and/or other factors indicated by the protocol. The received packet may be utilized by the node or retransmitted. The multiple protocol receiver may return to the first state to repeat and continue the procedure.

Abstract: Provided are an apparatus for addition data transmission includes: an IF broadcasting signal generating unit receiving the broadcast data, and FEC and modulation of the received broadcast data to generate a broadcasting signal in an intermediate frequency (IF) band; an IF addition signal generating unit receiving the addition data to generate an addition signal in the IF band by using direct sequence spread spectrum (DSSS); an average power controlling unit controlling average power of the addition signal in the IF band; a signal combining unit combining the broadcasting signal in the IF band and the addition signal in the IF band to generate a combination signal; an RF upward converting unit upwardly converting the combination signal in a signal in a radio frequency (RF) band to a combination signal in the RF band; and a transmitting unit transmitting the combination signal in the RF band.

Abstract: A method and system for storing and transmitting data using variable pulse characteristics to represent ASCII or UNICODE characters, of the value of a string of data using a number base higher than 2. Pulse characteristics are modified to correspond to different data values. Pulse characteristics can include pulse durations, pulse spacings, pulse amplitudes, pulse phases, pulse polarities, pulse shapes and/or other pulse characteristics.

Abstract: Certain aspects of the present disclosure relate to a method for employing a special format for transmitting data blocks which allows parallel equalizations at a receiver. By applying parallel equalization operations, a clock at the receiver can operate at a fraction of the input signal's data rate, which is more practical in the case of very high data rates while power dissipation is also reduced.

Abstract: A voice input device includes: a mastery level identifying device identifying a mastery level of a user with respect to voice input; and an input mode setting device switching a voice input mode between a guided input mode and an unguided input mode. In the guided input mode, preliminary registered contents of the voice input are presented to the user. The input mode setting device sets the voice input mode to the unguided input mode at a starting time when the voice input device starts to receive the voice input. The input mode setting device switches the voice input mode from the unguided input mode to the guided input mode at a switching time. The input mode setting device sets a time interval between the starting time and the switching time in proportion to the mastery level.

Abstract: A receiver device for receiving a signal that comprises one or more periodic features, the receiver device comprising: a detector configured to listen to the signal during at least a first reception phase, and to be triggered when a feature of the signal is received so as to determine the time of reception of that feature; and a receiver configured to process time-limited segments of the signal so as to derive information from features of the signal received during those segments, the receiver being configured to be dependent on the detector such that after the first reception phase the timings of the time-limited segments processed by the receiver are dependent on the time of reception determined by the detector.

Abstract: A method of generating a pair of orthogonal sets with a spreading factor N for a direct sequence spread spectrum communication system, includes selecting a two-level autocorrelation sequence of a period of N?1, the two-level autocorrelation sequence including elements, each of which includes a value of 1 or 0, and obtaining binary sequences based on the two-level autocorrelation sequence. The method further includes obtaining quasi-orthogonal sets based on the two-level autocorrelation sequence and the binary sequences, and generating the pair of the orthogonal sets based on the quasi-orthogonal sets.

Abstract: Methods and systems for fast synchronization and data reception for frequency hopping wireless communication systems are disclosed. Aspects of one method may include receiving a plurality of RF signals corresponding to a plurality of hopping frequencies. The RF signals may be processed in parallel to determine a hopping sequence. For example, the plurality of RF signals may be down-converted to a corresponding plurality of IF or baseband signals. The down-converted signals may be combined together to a single combined signal, and the single combined signal may then be processed to determine the frequency hopping sequence.

Abstract: Apparatus and methods for distributing spurious tones through the frequency domain are disclosed. One such apparatus can include a dithering circuit configured to generate a sequence of numbers that exhibit statistical randomness and a variable frequency circuit configured to adjust a frequency of an output based on the sequence of numbers so as to spread energy of spurious tones in a frequency response of the output to lower a noise floor. In one example, spurious tones can be reduced in a negative voltage generator of a radio frequency (RF) attenuator.