Described herein are systems and methods for accurately estimating and removing a carrier frequency offset. One exemplary embodiment relates to a system comprising a frequency offset detection circuit detecting a carrier frequency offset in an optical signal, and a frequency testing circuit calculating an estimated frequency offset value of the carrier frequency offset, wherein the frequency testing circuit removes a carrier phase based on the estimated frequency offset value and recovers the optical signal. Another exemplary embodiment relates to a method comprising detecting a carrier frequency offset in an optical signal, calculating an estimated frequency offset value of the carrier frequency offset, removing a carrier phase based on the estimated frequency offset value, and recovering the optical signal.

Aspects of the subject disclosure may include, for example, a system including a frequency mixer that combines a signal and a carrier wave to form a combined signal, and a transmitter that generates a transmission based on the combined signal. The system can also include a coupling device that emits the transmission as an electromagnetic wave guided by an outer surface of a transmission medium. The electromagnetic wave can propagate longitudinally along the surface of the transmission medium and at least partially around the surface of the transmission medium. Other embodiments are disclosed.

The present invention relates to a wireless transmission system for signals intended more specifically for a domestic environment. It includes a central terminal comprising at least m transmission channels and n directive transmission antennas intended to transmit first signals at least one client terminal having at least one reception channel connected to a reception antenna in order to receive the first signals said central terminal and said client terminal communicating in a transmission channel having a predetermined frequency band, and an estimation device able to generate an item of information representative of the reception quality of first signals in at least one point of a predetermined geographic zone associated with the client terminal and a return channel in order to transmit said at least one item of information to the control means of the central terminal.

In a wireless network, plural downlink signals from plural base stations are transmitted to a terminal. The plural downlink signals all carry the same information to the terminal. The terminal provides feedback on the downlink channels. The feedback provides information on the taps of the channels. The amount of information fed back is constrained. Based on the feedback, transmission parameters of the downlink signals are adjusted. The process of transmitting, providing feedback, and adjusting the parameters continue so that the energy of the downlink signal is enhanced at the terminal location and suppressed elsewhere. Beam forming can be used to further suppress the energy signature at locations other than the terminal location.

A method of calibrating an envelope tracking system for a supply voltage for a power amplifier module within a radio frequency (RF) transmitter module. The method includes deriving a mapping function between an instantaneous envelope of a waveform signal to be amplified by the power amplifier module and the power amplifier module supply voltage to achieve a constant power amplifier module gain based on a gain compression factor, setting an envelope tracking path of the transmitter module into an envelope tracking mode in which mapping between the instantaneous envelope of the waveform signal and the power amplifier module supply voltage is performed using the derived mapping function, applying a training signal comprising an envelope that varies with time to the RF transmitter module, measuring a battery current, modifying the gain compression factor based on the measured battery current, and re-deriving the mapping function based on the modified gain compression factor.

A mobile wireless device maintains a radio sector database. When receiving no response or a negative response from a radio sector to a transmitted signaling message, the mobile wireless device adds or updates the radio sector database. When receiving a positive response from the radio sector, the mobile wireless device deletes the radio sector from the radio sector database. Before transmitting signaling messages to a radio sector, the mobile device determines a time delay value if the radio sector is in the radio sector database. The mobile wireless device discards the signaling message when an elapsed time since a most recently transmitted signaling message to the radio sector does not exceed the determined time delay value. In an embodiment, each radio sector in the radio sector database includes a failure count value, and the determined time delay value depends on the failure count value.

A communication device and a power control method thereof are provided. The power control method, performed by a communication device, includes: determining a power range of a transmit power of an uplink signal; determining a gain switch range based on the power range; when the transmit power of the uplink signal is within the gain switch range, determining a first gain mode for amplifying the uplink signal; and when the transmit power of the uplink signal is out of the gain switch range, determining a second gain mode for amplifying the uplink signal.

A coupling device for use in a hybrid fiber coaxial (HFC) network may be configured to disable an upstream path through it when there is only noise incident on the upstream path, and enable the upstream path through it when a desired transmission from a cable modem downstream of the coupling device is incident on the upstream path. The coupling device may be a trunk amplifier, a distribution amplifier, a splitter, or the like. The coupling device may comprise a single upstream interface coupled to a plurality of downstream interfaces. The enabling and/or disabling may be in response to a signal strength indicated by the SSI being below a threshold and/or in response to one or more control messages indicating whether any downstream cable modem is, or will be, transmitting.

In order to transmit a large amount of data in series at a time with a MIMO communication scheme while avoiding deterioration of decoding characteristics due to change over time by a channel matrix, a wireless communication system uses an open-loop type and a closed-loop type of MIMO communication modes in combination and switches to the open-loop MIMO communication mode in response to the information that the amount of data to be transmitted at a time has exceeded a predetermined amount of bits or a predetermined transmission time during data transmission under the closed-loop MIMO communication mode. By discontinuing useless closed-loop MIMO communication and switching to the open-loop MIMO communication mode that is better than Zero-forcing, the decoding characteristics are prevented from simply becoming deteriorated.

Techniques for extracting the characteristic response of a non-linear channel are presented. In various implementations of the invention, a channel's characteristic response may be determined by identifying a first input sequence, determining the ones compliment of the first input sequence and then determining the response of the channel to these two input sequences. Subsequently, two input matrices and two response matrices may be generated based upon the two input sequences and their corresponding responses. Given these four matrices, a symmetrical response component may be determined by iteratively solving a system of equations formed from the columns of each matrix. Subsequently, given the symmetric component and these four matrices, an asymmetrical response component may be determined by again iteratively solving the system of equations for the columns of each matrix.

Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N−1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

Multiple-Input and Multiple-Output (MIMO)-Orthogonal Frequency Division Multiplexing (OFDM) communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy.

Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

In this VSWR measurement circuit, a power measurement unit measures the power level of a reflected signal which is included in a feedback signal which has been extracted at a second CPL which has been deployed at a position connecting to an antenna end via a cable. To this end, the VSWR measurement circuit is provided with a main signal component removal circuit, wherein the main signal which has been extracted from the prestage of a digital pre-distortion circuit, and a signal in which the feedback signal that had been extracted at the second CPL has been converted to a digital signal at an A/D CONV, are provided as inputs, the main signal component included in the feedback signal is removed, and only the reflected signal is extracted so as to be output to the power measurement unit.

A radio communication device capable of randomizing both inter-cell interference and intra-cell interference. In this device, a spreading section (214) primarily spreads a response signal in a ZAC sequence set by a control unit (209). A spreading section (217) secondarily spreads the primarily spread response signal in a block-wise spreading code sequence set by the control unit (209). The control unit (209) controls the cyclic shift amount of the ZAC sequence used for the primary spreading in the spreading section (214) and the block-wise spreading code sequence used for the secondary spreading in the spreading section (217) according to a set hopping pattern. The hopping pattern set by the control unit (209) is made up of two hierarchies. An LB-based hopping pattern different for each cell is defined in the first hierarchy in order to randomize the inter-cell interference. A hopping pattern different for each mobile station is defined in the second hierarchy in order to randomize the intra-cell interference.

A decoder receives a bitstream containing quantized coefficients representative of blocks of video representative of a plurality of pixels and decodes the bitstream using context adaptive binary arithmetic coding that includes at least two decoding modes, the first mode decoding the bitstream based upon a probability estimate which is based upon at least one of spatially and temporally adjacent syntax element values to a current syntax element being decoded, the second mode decoding the bitstream not based upon a probability estimate based upon other syntax elements to the current syntax element being decoded. The coding decodes the current syntax element using the first mode if the current syntax element is intra-coded and selecting between sets probable modes with different probabilities. The coding decodes the current syntax element using the second mode if the current syntax element is intra-coded and if selecting among one of the second set of probable modes.

A method includes extracting a first vector used to code a specific block belonging to a coded field picture arranged chronologically adjacent to a field picture to be coded and to a block to be coded, generating a second vector by scaling the first vector based on a temporal distance between the field picture and a second picture specified by a reference index and referenced for the block and included in the field picture and a temporal distance between a first picture pointed by the first vector and the coded field picture arranged chronologically adjacent to the field picture, and correcting the second vector based on a parity of the field picture, a parity of the first picture, a parity of the second picture and a parity of the coded field picture and forming the corrected second vector.

A transport stream (TS) generating apparatus, a transmitting apparatus, a receiving apparatus, a digital broadcast system having the above, and a method thereof are provided. The digital broadcast system includes a transport stream (TS) generating apparatus which generates a multi transport stream (TS) by multiplexing a normal stream and a turbo stream having a variable coding rate, a transmitting apparatus which re-constructs the multi TS by processing the turbo stream, and transmits the re-constructed multi TS, and a receiving apparatus which receives the re-constructed multi TS, and decodes the normal stream and the turbo stream respectively, to recover normal data and turbo data. Accordingly, a multi TS, which includes normal stream and a turbo stream of various coding rates, can be transmitted and received efficiently.

Various methods and systems for efficiently performing the blind decoding of downlink signals is described. Several forms of arranging possible CCE combinations are examined and investigated. Based on PDCCH size estimation/information, CCE concatenations that are most likely (of of limited sets) can be arrived at. Tree-based concatenations are also devised using largest CCE ordering to align smaller CCE sizes to similar boundaries. By such ordering, the search space for all possible CCE ordering and sizes can be reduced to an efficient tree. Set mapping between possible lnposelstartCCElnposelend/REs are also described using a first set to secondary and tertiary sets. Various other ordering and sorting schemes are also detailed that enable a blind decode of a PDCCH channel to be efficiently performed.

A method is provided for improving synchronization and information transmission in a communication system, including: generating a signal with a centrally symmetric part s(k) exploitable for synchronization; and sending the signal over a communication channel. The signal is based on a uniquely identifiable sequence c(l) from a set of sequences exploitable for information transmission. The centrally symmetric part s(k) is centrally symmetric in the shape of absolute value thereof. The centrally symmetric part s(k) is of arbitrary length N.

A method and device that interrogates the availability of a called party before placing a communication from the calling party to the called party. A callback may be initiated so that both communications are completed simultaneously. The routing of communication may take place through any one of a number of different networks and at another time of the day, even if the caller does not otherwise have access to those networks.

A transceiver includes an antenna, an impedance adjustment device, an RF (Radio Frequency) front-end circuit, a storage device, and a processor. The antenna receives an RF signal. The impedance adjustment device is coupled to the antenna, and includes a plurality of branch circuit with different impedance values and a switch module. The processor is coupled to the RF front-end circuit and controls the switch modules. In a comparison mode, the switch module selects to connect to the branch circuits individually, and the processor detects each RSSI (Received Signal Strength Indications) value corresponding to the branch circuit and records all of the RSSI values to the storage device respectively. In the comparison mode, the processor further compares the RSSI values to for highest one. Finally, the switch module selects the branch circuit corresponding to the highest RSSI value as a transmission branch.

Embodiments of the present disclosure are directed towards a circuit board having integrated passive devices such as inductors, capacitors, resistors and associated techniques and configurations. In one embodiment, an apparatus includes a circuit board having a first surface and a second surface opposite to the first surface and a passive device integral to the circuit board, the passive device having an input terminal configured to couple with electrical power of a die, an output terminal electrically coupled with the input terminal, and electrical routing features disposed between the first surface and the second surface of the circuit board and coupled with the input terminal and the output terminal to route the electrical power between the input terminal and the output terminal, wherein the input terminal includes a surface configured to receive a solder ball connection of a package assembly including the die. Other embodiments may be described and/or claimed.

A circuit card is provided that includes ground traces that extend from a resistor to a commoning bar, where a resultant electrical length between the resistor and the commoning bar and is configured to reduce energy carried on the ground terminals that could otherwise result in cross-talk. In an embodiment, the ground trace may be configured in a meandering manner. In another embodiment, the ground trace may be split and joined by an inductor.

A balun including a first conductor winding, a first inductor, a second inductor, a third inductor, and a fourth inductor. The first conductor winding has a figure eight shape including a first loop and a second loop. The first inductor and the second inductor substantially surround the first loop. The third inductor and the fourth inductor substantially surround the second loop.

A transmission line is provided in which a first portion of the transmission line is configured to be connected to a source, and a second portion of the transmission line is configured to be connected to a load. A capacitive element is coupled to the transmission line and is configured to compensate for an impedance difference between the load and at least one of the source or the transmission line, at a frequency within a frequency bandwidth of the load. A difference between an internal capacitance of the first portion of the transmission line and the second portion of the transmission line substantially matches the capacitance of the capacitive element.

The present invention is directed to an impedance transformation device for use in a system having a characteristic system impedance, the device being characterized by a predetermined bandwidth having a center frequency. The device housing size is one-eighth wavelength of the center frequency. A first coupler is characterized by an even mode impedance and an odd mode impedance. The bandwidth is a function of the even mode impedance and the odd mode impedance substantially corresponds to the component port impedance. At least one second coupler is disposed in parallel with the first coupler and is characterized by the even mode impedance and the odd mode impedance.

There is provided a high frequency switch having a reduced circuit scale while maintaining satisfactory harmonic characteristics in a transfer path of a high frequency signal. The high frequency switch includes: at least one transmission port; at least one reception port; a common port; transmission side series switches each including a body contact type FET; transmission side shunt switches each including a body contact type FET; reception side series switches each including a body contact type FET; and reception side shunt switches each including at least one floating body type FET.

A balun transformer includes an unbalanced terminal, two balanced terminals, a directional coupler, a low pass filter, and a high pass filter. The directional coupler includes first, second, third and fourth terminals. The first terminal is connected to the unbalanced terminal. A predetermined phase difference exists between the output signal of the second terminal and the output signal of the third terminal. The second terminal is connected to the first terminal by a line constituting the directional coupler. The low pass filter is connected between the second terminal and one of the balanced terminals. The high pass filter is connected between the third terminal and the other balanced terminal.

A directional coupler includes in a laminate block, a first main line, a first sub-line, a second sub-line, and a second main line sequentially provided in a lamination direction of layers. Further, each of the first main line, the first sub-line, the second sub-line, and the second main line is divided into at least two divided coil conductors. Furthermore, at least two divided ground conductors are provided between the first sub-line and the second sub-line.

A three dimensional (3D) branchline coupler using through silicon vias (TSV), methods of manufacturing the same and design structures are disclosed. The method includes forming a first waveguide structure in a first dielectric material. The method further includes forming a second waveguide structure in a second dielectric material. The method further includes forming through silicon vias through a substrate formed between the first dielectric material and the second dielectric material, which connects the first waveguide structure to the second waveguide structure.

A duplexer has an antenna terminal, a first terminal, and second terminals and provided with a first filter arranged between the antenna terminal and first terminal and including a parallel resonator for forming a ladder type filter circuit, a second filter arranged between the antenna terminal and the second terminal and having a passband higher than a passband of the first filter, and an electromagnetic coupling element arranged between the parallel resonator of the first filter and a ground part and electromagnetically coupled with the antenna terminal.

A ladder filter includes at least one series resonator connected in series between an input terminal and an output terminal, at least one parallel resonator connected in parallel with the at least one series resonator, an additional resonator connected in series between the at least one series resonator and one of the input terminal and the output terminal, and an inductor connected in series to the additional resonator, the additional resonator having a resonance frequency higher than an anti-resonance frequency of the at least one series resonator.

The present invention discloses a filter for removing noise, which includes: a lower magnetic substrate; a coil layer disposed on the lower magnetic substrate and including at least one conductor pattern and an insulating layer covering the conductor pattern; an upper magnetic substrate disposed on the coil layer; and a magnetic permeability enhancing layer disposed on the magnetic substrate with lower magnetic permeability of the lower magnetic substrate and the upper magnetic substrate. According to the present invention, it is possible to implement a filter for removing noise with high performance, characteristics, and reliability by increasing magnetic permeability to improve impedance characteristics and improving an effect of shielding electromagnetic waves such as jamming.

In a multilayer band pass filter, via-electrodes and strip electrodes define inductors of LC parallel resonators in four stages. A capacitor electrode and a ground electrode define a capacitor of a first-stage LC parallel resonator. A capacitor electrode and the ground electrode define a capacitor of a fourth-stage LC parallel resonator. Capacitor electrodes define a second-stage LC parallel resonator. Capacitor electrodes define a third-stage LC parallel resonator. Among four or more of the LC parallel resonators, the coupling between certain LC parallel resonators is easily defined, and the attenuation characteristic of a filter is definable with a high degree of freedom.

An acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode provided on an upper surface of the piezoelectric substrate, a first dielectric film covering the upper surface of the piezoelectric substrate to cover the IDT electrode, and a second dielectric film covering an upper surface of the first dielectric film. The second dielectric film includes a thin portion positioned in a tip region of electrode fingers of the IDT electrode and a thick portion which is positioned in a middle region of the IDT electrode and is thicker than the thin portion. The acoustic wave device suppresses spurious emission and has superior passband characteristics.

A SAW filter circuit having improved ESD resistance is specified, in which a series interconnection composed of SAW resonators is interconnected between a first signal port and a dual-mode SAW filter port. The static capacitance of the series interconnection is at most four times the static capacitance of the dual-mode SAW filter transducers interconnected therewith.

A frequency tunable filter is disclosed. The frequency tunable filter includes a filter unit that can tune a frequency band of a frequency signal being filtered, a communication module that receives a control signal for controlling the tuning of the frequency band, and a control unit that controls the tuning of the frequency band based on the control signals. The disclosed filter can control the tuning of the filter's frequency band wirelessly.

In an example embodiment, an electromagnetic interface can comprise: a first component comprising a first waveguide channel, a first interface surface, and a first force transfer feature; a second component comprising a second waveguide channel, a second interface surface, and a second force transfer feature; and a fastener that can be configured to force the first force transfer feature in sliding engagement with the second force transfer feature. The first and second force transfer features can be configured to interoperate to create an indirect force holding the first interface surface in contact with the second interface surface and holding the first waveguide channel in alignment with the second waveguide channel.

A right circular cylindrical body of an isotropic dielectric such as a cross-linked styrene copolymer, has respective pluralities of mutually parallel grooves formed in its axial end faces, spaced apart by an intermediate portion whose dimension c is a half wavelength. The axial lengths a, b of the grooves are such that when a wave passes through the body, a quarter wavelength phase difference is produced between a component of a wave having its E-vector parallel to the grooves and a component of the wave having its E-vector orthogonal to the grooves. Alternatively the plate may consist of two or more discrete bodies whose grooves are dimensioned to produce a total differential phase shift of one quarter wavelength.

A power supply apparatus includes a converter to convert AC power into DC power, an SMPS to convert the DC power into DC powers desired by loads, a capacitor to interconnect the converter and the SMPS, a PTC element connected to the converter, a first switch connected in parallel with the PTC element, and a second switch connected in series with the first switch. The method includes turning on the second switch to start charging of the capacitor, turning on the first switch to charge the capacitor to a target voltage level, and turning off both the first switch and second switch if a voltage across the capacitor rises over the target voltage level, to discharge the voltage across the capacitor so as to lower the voltage across the capacitor to the target voltage level or lower.

A radio frequency (RF) generation system includes an impedance determination module that receives an RF voltage and an RF current. The impedance determination module further determines an RF generator impedance based on the RF voltage and the RF current. The RF generation system also includes a control module that determines a plurality of electrical values based on the RF generator impedance. The matching module further matches an impedance of a load based on the RF generator impedance and the plurality of electrical components. The matching module also determines a 2 port transfer function based on the plurality of electrical values. The RF generation system also includes a virtual sensor module that estimates a load voltage, a load current, and a load impedance based on the RF voltage, the RF generator, the RF generator impedance, and the 2 port transfer function.

The present invention provides an artificial microstructure employed in an artificial electromagnetic material. The artificial microstructure includes a first segment, a second segment, and a third segment. The first segment is parallel to the second segment, and the third segment is connected between the first segment and the second segment. The artificial electromagnetic material has a special electromagnetic effect. The artificial electromagnetic material can be applied to various electromagnetic application systems instead of the typical electromagnetic material.

An attenuation reduction control structure for high-frequency signal transmission lines of a flexible circuit board includes an impedance control layer formed on a surface of a substrate. The impedance control layer includes an attenuation reduction pattern that is arranged in an extension direction of the high-frequency signal transmission lines of the substrate and corresponds to bottom angle structures of the high-frequency signal transmission lines in order to improve attenuation of a high-frequency signal transmitted through the high-frequency signal transmission lines. An opposite surface of the substrate includes a conductive shielding layer formed thereon. The conductive shielding layer is formed with an attenuation reduction pattern corresponding to top angle structures of the high-frequency signal transmission lines.

An attenuator includes, on a substrate: a resistor section; an insulating film covering the resistor section; and connection terminals covering the insulating film and connected in part to the resistor section. A total thickness of the insulating film and the connection terminal in a region where the insulating film and the connection terminal overlap with the resistor section is from 50 μm to 200 μm.

Embodiments of resonator circuits and modulating resonators and are described generally herein. One or more acoustic wave resonators may be coupled in series or parallel to generate tunable filters. One or more acoustic wave resonances may be modulated by one or more capacitors or tunable capacitors. One or more acoustic wave modules may also be switchable in a filter. Other embodiments may be described and claimed.

An electronic component includes: a first circuit connected to a first common terminal for inputting/outputting a first signal set, a second common terminal for inputting/outputting a second signal set having a frequency higher than the first signal set, and a third common terminal for being connected to an antenna; and a second circuit connected in parallel to the first circuit between the first and second common terminals, wherein the first circuit includes a first filter transmitting the first signal set and reflecting the second signal set, and a second filter transmitting the second signal set and reflecting the first signal set, the third common terminal is located between the first and second filters, and the second circuit reflects a first transmission signal and a second transmission signal, transmits parts of the first and second transmission signals, and inverts phases of the parts of the first and second transmission signals.

An object of the present invention is to improve the passing characteristic at high temperature in a ladder-type elastic wave filter and a duplexer including the filter. The ladder-type elastic wave filter of the present invention includes a piezoelectric substrate, a first series elastic-wave resonator formed on the piezoelectric substrate and connected in series between the input and output terminals of the filter, a parallel elastic-wave resonator formed on the piezoelectric substrate and connected in parallel between the series elastic-wave resonator and the ground terminal, and a dielectric film formed on the piezoelectric substrate so as to cover the first series elastic-wave resonator. The piezoelectric substrate is formed of a material with a negative temperature coefficient. The dielectric film is formed of a material with a positive temperature coefficient and its film thickness is formed thicker than that with which the frequency-temperature coefficient of the first series elastic-wave resonator becomes 0.

An SAW filter and a duplexer excellent in electrical characteristics will be provided. An SAW filter has a piezoelectric substrate 40, a surface acoustic wave element 10 having a first IDT electrode 1 on the piezoelectric substrate 40, a first signal line 31 electrically connected to the first IDT electrode 1, and a ring-shaped reference potential line 9 which has a first intersecting portion intersecting with the first signal line 31 through an insulation member 41 and surrounds the surface acoustic wave element 10.

A waveguide busbar for conducting microwaves includes a group input for coupling in a group microwave signal, a plurality of filter inputs for coupling in a plurality of microwave signals, a dual waveguide that comprises a first single waveguide and a second single waveguide. The plurality of filter inputs are disposed along the dual waveguide, as well as at least one adjustable coupling member that provides a connection between the first single waveguide and the second single waveguide and that is configured such that it adjusts a phase length of the connection.