Abstract: A communication system includes a plurality of communication stations arranged to respectively transmit a beacon on which beacon time information related to a beacon received from a peripheral communication station is placed at a predetermined transmission interval and control a beacon transmission timing of its own station while a collision with the beacon transmitted from the peripheral communication station is avoided on the basis of beacon information placed on the received beacon, in which at least a part of the communication stations includes means configured to decide a priority with respect to beacons received from at least one peripheral communication station and means configured to place beacon time information of a beacon having a high priority among the received beacons on a beacon of its own station, and transmits the beacon at a predetermined transmission interval.

Abstract: Present document is related with communication of synchronization signals between base station and terminal. The base station acquires a primary synchronization signal generated using a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence having a root index M and having a length L, and a secondary synchronization signal informing a cell group ID. And, the base station transmits the primary synchronization signal at a last symbol of a specific time domain unit to one or more terminals, and the secondary synchronization signal at a second-to-last symbol of the specific time domain unit to the one or more terminals. Here, the root index M is one among a root index set comprising m0 and m1 meeting “m0+m1=(½*L)*n” or “m0?m1=±(½*L)*n”, where ‘n’ is an integer greater than 0.

Abstract: Systems, methods, and other embodiments associated with detecting an event are described. According to one embodiment, a device includes a detect logic that is configured to, during a sample window, monitor a communication channel for an event in a signal, wherein monitoring the communication channel for the event includes incrementing a counter in response to a magnitude of the communication channel being greater than a first predetermined threshold, and provide a detection signal in response to the counter reaching a second predetermined threshold, wherein the detection signal indicates detection of the event in the signal.

Abstract: In a data transmission system, a first node receives at least two sets of input data signals including at least two signals being based on different synchronization sources. The first node extracts a respective clock signal representing the embedded clock signals from the sources, samples and formats these signals for transmission according to a TDM structure. The TDM formatted signals are transmitted as at least one bit stream over a transmission medium to at least one second node, where the bit stream is demultiplexed into at least two sets of output data signals respective demultiplexed clock signals representing the sampled clock signals. A jitter attenuating mechanism reduces an amount of frequency jitter to below a predefined level to produce a respective clock signal having a synchronization quality superior to that of the demultiplexed clock signals. An interface module recombines each data signal with its associated clock signal.

Abstract: A time synchronization method includes: after sending a synchronization message to the opposite end, sending a following message where an ending time for sending the synchronization message is recorded; receiving a delay request message sent by the opposite end, and sending a delay response message where the initial time for receiving the delay request message is recorded; receiving the synchronization message and the following message, and recording the initial time for receiving the synchronization message and the ending time recorded in the following message for sending the synchronization message; sending a delay request message, and recording an ending time for sending the delay request message; receiving a delay response message, and recording an initial time recorded in the delay response message for the opposite end to receive the delay request message; calculating the time offset value between the two ends, and completing time synchronization.

Abstract: A beamforming training (BFT) data unit for transmission via a communication channel in a wireless personal area network is generated, and in particular, is for transmitting beamforming training information. A physical layer header and first BFT data are encoded using block encoding to generate a first block. Second BFT data are encoded using block encoding to generate a second block. The BFT data unit is generated with a fixed-length payload, such that the BFT data unit includes only i) a preamble, ii) the first block, and iii) the second block.

Abstract: A transmission system which couples a plurality of transmission devices to a control device includes a first transmission device which is one of the plurality of transmission devices; a first calculation circuit which calculates a first difference value indicating a frequency difference value between a common clock supplied from the control device and a first clock as a clock used in the first transmission device; and a transmitter which reports the first difference value to a second transmission device other than the first transmission device, wherein the second transmission device comprises: a second calculation circuit which calculates a second difference value indicating a frequency difference value between the common clock and a second clock used in the second transmission device, and a frequency controller which controls an oscillator generating the second clock so that the second difference value approaches the first difference value reported from the first transmission device.

Abstract: A timing source is provided for sending timing information via a packet network. The source comprises a first clock for generating the timing information and a packet forming section for forming a sequence of packets. An output section in the form of a packet launch control section transmits the packets via the network as packet bursts, each of which comprises a plurality of packets with the intervals between consecutive packets of each burst being less than the intervals between consecutive packets. A time-stamping section inserts into each packet a transmission time derived from the timing information generated by the clock.

Abstract: Apparatuses, circuits, and methods are disclosed for reducing or eliminating unintended operation resulting from metastability in data synchronization. In one such example apparatus, a sampling circuit is configured to provide four samples of a data input signal. A first and a second of the four samples are associated with a first edge of a latching signal, and a third and a fourth of the four samples are associated with a second edge of the latching signal. A masking circuit is configured to selectively mask a signal corresponding to one of the four samples responsive to the four samples not sharing a common logic level. The masking circuit is also configured to provide a decision signal responsive to selectively masking or not masking the signal.

Abstract: A method for uplink synchronization in a multi-carrier system includes the following steps: a base station selects one or more first component carriers, which do not establish the uplink synchronization with the base station, from multiple component carriers supported by a terminal; then the base station obtains Timing Advance (TA) needed by the terminal to perform the uplink transmission on the first component carriers, and sends the TA information to the terminal; the terminal performs the uplink transmission on said first component carriers according to said TA. The application of the present invention enables the establishment of uplink synchronization between the base station and the user equipment in multi-carrier system.

Abstract: A clock and data recovery device receives a serial data stream and produces recovered clock and data signals. The clock and data recovery device operates over a range of frequencies and without use an external reference clock. A first loop supplies a first clock signal to a second loop. The second loop modifies the first clock signal to produce the recovered clock signal and uses the recover clock signal to produce the recovered data signal. The first loop changes the frequency of the first clock signal based on frequency comparison and data transition density metrics.

Abstract: A base station transmits on a first control channel first scheduling information for a control message. First radio resources of the first control channel start from the first symbol of each subframe in a plurality of subframes. The base station transmits the control message configuring second radio resources of a second control channel. The second radio resources comprise resource blocks in a subset of subframes in the plurality of subframes. The control message indicates the subset of subframes and a starting symbol of the second control channel. The base station transmits second scheduling information on the second control channel.

Abstract: Exact data-rate analysis of the information signal portions to be transmitted in a subsequent transmission cycle per time-division multiplexing process shall be initially omitted. Instead, on the basis of highly accurate estimated values for the subsequent data rates, estimated values for relative waiting times are transmitted, in a current transmission cycle, from the current time slice to the subsequent time slice of the same service. In the subsequent transmission cycle, actual data rates may be set which may deviate from the estimated data rates for the individual information signals, as a result of which predicted time-slice boundaries for the subsequent transmission cycle may shift. However, the potential shift in the time-slice boundaries is subject to several boundary conditions. No time slice of the subsequent transmission cycle can start prior to its signaled estimated starting time. With constant data rates, the estimated time-slice structure and the actual time-slice structure are identical.

Abstract: A method (400) for creating a group shared distributed reservation in a wireless network. The method comprises collecting information about the distributed reservation availabilities of devices in the wireless network (S410); selecting a group of shared devices to be included in the group shared distributed reservation based on the collected information (S420); sending a reservation request to each device in the group of shared devices (S430); and updating the group of shared devices to include only devices that accept the reservation request (S460), thereby creating a group shared distributed reservation of medium access time slots.

Abstract: A system including an input module, a first gain module, a second gain module, and a preamble estimation module. The input module is configured to receive an input signal from a station. The input signal includes (i) a first preamble sequence, and (ii) subcarriers. The first gain module is configured to, based on the input signal, generate first channel gain values. Each of the first channel gain values is for a respective one of the subcarriers. A second gain module is configured to, based on the first channel gain values, generate second channel gain values. A preamble estimation module is configured to estimate the first preamble sequence based on (i) the first channel gain values, and (ii) the second channel gain values.

Abstract: A digital subscriber line (DSL) unit comprises a first user port configured to communicate signals according to an Ethernet protocol and a second user port configured to communicate signals according to a second non-Ethernet protocol The DSL unit also comprises at least one DSL port configured to communicate signals according to a DSL protocol; and a processing device configured to analyze Ethernet signals received over the first user port to determine when to output data from the respective received Ethernet signals over the second user port and when to output data from the respective received Ethernet signals over the at least one DSL port. The processing device is further configured to extract data from signals received over the second user port and insert the extracted data into a corresponding Ethernet signal having a respective emulated circuit identification and to output the corresponding Ethernet signal over the first user port.

Abstract: A method for detecting a channel in a mixed-mode communications system is presented. The channel contains a primary synchronization pattern in a predetermined location within the channel. The primary synchronization pattern is compared against different predetermined channel synchronization patterns to detect a channel. Upon detection of the channel, a look-back channel detector confirms the existence of the channel by using the location of the primary synchronization pattern. Detection and confirmation of the channel may be employed simultaneously to each channel of a multiple-channel direct mode of operation signal. Audio holes may be eliminated in a 2:1 TDMA direct mode operation where both time slots contain signals from two different originating communication devices and the signals have different priority.

Abstract: The present invention provides a method for range extension is wireless communication systems. One embodiment of the method includes determining whether a mobile unit is within a first range corresponding to a range of timing advances supported by a timing advance command. This embodiment also includes transmitting a plurality of timing advance commands to the mobile unit when the mobile unit is outside the first range so that the mobile unit can synchronize with the base station by combining information in the plurality of timing advance commands.

Abstract: A system including a demodulation module, a metric generation module, and a preamble detection module. The demodulation module is configured to generate demodulated signals based on demodulating, in accordance with a differential demodulation scheme, signals received from a base station. The signals received from the base station include a plurality of symbols. The demodulated signals comprise a plurality of real parts each having a corresponding magnitude. The metric generation module is configured to generate a plurality of metrics for the plurality of symbols based on the corresponding magnitudes of the plurality of real parts of the demodulated signals. The preamble detection module is configured to detect, based on the plurality of metrics, whether the plurality of symbols in the signals received from the base station includes a preamble symbol.

Abstract: Apparatus and methods relating to synchronization of communication equipment are disclosed. Synchronization information received from a bonded communication link can be used to synchronize local and/or remote communication equipment, such as femtocell sites coupled to nodes in a ring network. This may involve isolating a frequency reference signal from a DSL (Digital Subscriber Line) communication link which is a constituent link of a bonded communication link, for example. In a ring network, received synchronization information could be used in synchronizing a locally connected installation of communication equipment, and passed for transmission in the ring network for synchronizing other communication equipment. Such dropping and passing of an analog frequency reference signal could be applied in networks having other topologies as well. At least some embodiments of the invention are applicable to optical links.

Abstract: A data Interface for transferring digital data between a host and a client over a communication path using packet structures linked together to form a communication protocol for communicating a pre-selected set of digital control and presentation data. The signal protocol is used by link controllers configured to generate, transmit, and receive packets forming the communications protocol, and to form digital data into one or more types of data packets, with at least one residing in the host device and being coupled to the client through the communications path. The interface provides a cost-effective, low power, bi-directional, high-speed data transfer mechanism over a short-range “serial” type data link, which lends itself to implementation with miniature connectors and thin flexible cables which are especially useful in connecting display elements such as wearable micro-displays to portable computers and wireless communication devices.

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 video transmission method is provided, which includes receiving state information from at least one mobile terminal that intends to perform a video stream service through a wireless network, determining a size of an image by selecting a specified spatial layer bit stream on the basis of the state information of the mobile terminal from a plurality of spatial layer bit streams generated at different bit rates during encoding of the bit stream, selecting a specified time and an SNR layer bit stream by increasing or decreasing time of the image and a layer position of the SNR layer bit stream on the basis of network parameters included in the state information of the mobile terminal, and transmitting the bit stream generated by extracting the specified layer bit stream of the selected layer to the mobile terminal.

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: The invention relates to a technique for controlling a synchronization of a terminal device (10) with a wireless network, e.g. an LTE network, wherein data are transmitted as a continuous data signal on a radio interface (11, 12) while being processed block-wise in the terminal (10). A method embodiment of the technique for achieving at least a downlink (11) synchronization comprises establishing a time-address mapping (TAM, 36) indicative of an association of a reference time value of an internal clock (32) with a reference address in the reception data buffer (16); determining an address of data samples representing the received data block in the reception data buffer (16) based on the time-address mapping; and initiating a block-wise reading of the data block from the reception data buffer (16) based on the determined address.

Abstract: A base station apparatus determines which mode of a subframe bundling mode (second mode) and a non-bundling mode (first mode) should be used by a user apparatus for communication, and reports a determination result. In the first mode, RTT period is a first period, and each of transmission and retransmission of the signal is performed every 1 TTI. In the second mode, RTT period is a second period that is longer than the first period, and each of transmission and retransmission of the signal is performed every plurality of TTIs. A radio resource to be used for retransmission is determined according to a first frequency hopping pattern in the first mode, and is determined according to a second frequency hopping pattern that is different from the first frequency hopping pattern in the second mode.

Abstract: The embodiments provide an additional information insertion apparatus for a broadcasting system. The system includes a broadcasting signal transmitter configured to transmit a broadcasting signal along with a data extractor configured to extract a modulated signal by dividing the modulated signal from a modulator of the broadcasting signal transmitter. An additional data generator is configured to extract synchronization of the broadcasting signal from the extracted broadcasting signal, modulate the additional information based on the extracted synchronization, and generate a level of the modulated additional information to be a smaller level than a signal level of the modulated signal by as much as a predetermined value. A data synthesizer is provided to insert the additional data from the data generator into the modulated broadcasting signal.

Abstract: Provided are an apparatus and method of transmitting and receiving a wake-up signal. The method of receiving a wake-up signal includes the following: operating a radio frequency (RF) receiving unit that receives a wireless signal through an antenna during an SFD detecting time, wherein the SFD detecting time is shorter than a predetermined SFD detecting time period, according to the predetermined SFD detecting time period and detecting a start of frame delimiter (SFD) to indicate that the received wireless signal is a wake-up signal to wake-up a node in a sleep mode; and detecting the wake-up signal by continuously operating the RF receiving unit when the SFD is detected. Power consumption that is used to receive the wake-up signal can be reduced.

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: Techniques are described that can be used to extend the data transmission rate specified by 10GBASE-KR of IEEE 802.3ap (2007) to more than 10 Gb/s using a multiple lane backplane. A signal for transmission over 10 Gb/s can be divided into multiple streams for transmission over multiple lanes. Multiple transceiver pairs can be used for transmission and receipt of the multiple streams. Each transceiver pair may comply with 10GBASE-KR of IEEE 802.3ap (2007).

Abstract: In one embodiment, receiving an Ethernet signal over a channel, the Ethernet signal comprising a preamble frame, an idle frame, and a data frame, the preamble frame comprising one or more preamble codes; synchronizing to the Ethernet signal based on the preamble frame; replicating the one or more preamble codes; and training a decision feedback equalizer (DFE) based on the one or more replicated codes, the training enabling the DFE to use decision values at the DFE output to track channel variations.

Abstract: Generate a series of digital data according to a pair of differential signals received from a low speed universal serial bus. Calibrate coarsely a frequency of an oscillator according to a width of an end-of-packet of the series of digital data. And calibrate finely the frequency of the oscillator according to a width of a SYNC pattern of the series of digital data.

Abstract: Two clocks may be synchronized by calculating skew and offset values that may be determined from several correlation events. A correlation event may be the passing of messages in both directions between the two devices. The skew and offset values may be used to determine the time of non-correlated events. The clock synchronization may be performed on a real time basis or may be performed on a post processing basis. One method for calculating the skew and offset may use inequalities within a solution space to refine a solution set with multiple sets of correlation events.

Abstract: A radio communication apparatus that performs radio communication with another communication apparatus includes an antenna unit, a contact detecting unit that detects contact with the another communication apparatus, a first modulating and demodulating unit for performing communication in a state in which the radio communication apparatus is remote from the another communication apparatus, a second modulating and demodulating unit for performing communication in a state in which the radio communication apparatus is in contact with the another communication apparatus, and a control unit that performs control to perform radio communication with the another communication apparatus via the antenna unit by selecting the first modulating and demodulating unit while the contact detecting does not detect contact with the another communication apparatus and selecting the second modulating and demodulating unit when the contact detecting unit detects contact with the another communication apparatus.

Abstract: Methods and apparatuses are provided for facilitating distributed transmissions among a plurality of access terminals for a transmission sequence. An access point may assign a predecessor transmitter device for each of a plurality of access terminals, and may transmit to each access terminal an instruction to follow a respective preceding transmission by the predecessor transmitter. An access terminal may receive the transmission including the instruction, and may monitor for and detect the preceding transmission. The access terminal may then transmit a transmission after the completion of an interframe space that may follow the detected preceding transmission.

Abstract: A radio system having multi-standard mixed mode radios is described. The mixed mode radios are used to support combining of digital baseband from a first and a second radio equipment controller. A primary clock associated with the first radio equipment controller and a secondary clock associated with the second radio equipment controller is provided. The quality of the primary clock is evaluated and the primary clock is referenced to the first radio equipment controller if the clock is determined to have appropriate quality factors. The quality of the secondary clock is then evaluated and the secondary clock is referenced to the second radio equipment controller if the secondary clock is determined to have appropriate quality factors. The second radio equipment controller is then referenced to the primary clock once the primary and secondary clocks are aligned.

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: In described embodiments, a transceiver includes a clock and data recovery module (CDR) with an eye monitor and a cycle slip monitor. The cycle slip detector monitors a CDR lock condition, which might be through detection of slips in sampling and/or transition timing detection. The cycle slip detector provides a check point to sense system divergence, allowing for a mechanism to recover CDR lock. In addition, when the CDR is out-of-lock, the various parameters that are adaptively set (e.g., equalizer parameters) might be invalid during system divergence. Consequently, these parameters might be declared invalid by the system and not used.

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: There is described a method for transmitting N parallel data flows on a parallel bus. The method comprises, at a first communication device: generating a further parallel data flow comprising alignment words periodically distributed with a period; at each period, rotating the N of parallel data flows and the further parallel data flow thus generating N+1 rotated parallel data flows, each comprising part of the alignment words periodically distributed with a frame period; transmitting the N+1 rotated parallel data flows on respective physical connections of the parallel bus. The method further comprises, at a second communication device: aligning the N+1 rotated parallel data flows by using the alignment words, thus compensating skew and obtaining N+1 aligned parallel data flows; and at each period, de-rotating the N+1 aligned parallel data flows, thus generating N de-rotated parallel data flows corresponding to the N parallel data flows.

Abstract: A wireless communication system of the present invention achieves improvement of reliability of communication of control data while suppressing the decrease in the communication throughput of data blocks and/or control data. The wireless communication system of the present invention is provided with a base station (1) and a mobile station (2). The mobile station (2) is configured to transmit a plurality of data blocks to the base station (1) at predetermined transmission time intervals. One of the base and mobile stations is configured to generate a plurality of control data used for control of transmission of said plurality of data blocks, to generate a plurality of control messages from said plurality of control data, and to transmit said plurality of control messages to the other of the base and mobile stations.

Abstract: A method for determining an overlap and add length estimate comprises determining a plurality of correlation values of a plurality of ordered frequency domain samples obtained from a data frame; comparing the correlation values of a first subset of the samples to a first predetermined threshold to determine a first edge sample; comparing the correlation values of a second subset of the samples to a second predetermined threshold to determine a second edge sample; using the first and second edge samples to determine an overlap and add length estimate; and providing the overlap and add length estimate to an overlap and add circuit.

Abstract: According to one embodiment, a frequency offset compensation apparatus includes a first estimation unit, a second estimation unit, a setting unit, a synthesis unit and a compensation unit. The first estimation unit estimates a first rotation. The second estimation unit estimates a second rotation. The setting unit sets a weighting factor for the second rotation to a first value if a received power is less than a threshold value, and sets the weighting factor for the rotation to a second value being smaller than the first value if the received power is not less than the threshold value. The synthesis unit calculates a compensation value. The compensation unit compensates for a frequency offset.

Abstract: The present invention relates to optical communications and discloses a master clock time synchronization method, slave clock time synchronization method, system and optical network device in a Passive Optical Network (PON) for the purpose of resolving time synchronization in Ethernet over Gigabit PON Encapsulation Method (GEM) mode. The PON master clock time synchronization method includes: predefining a rule for matching packet time stamp generating points; sending a first clock packet carried in a first downstream frame; acquiring time at a packet time stamp generating point that matches the frame data of the first downstream frame at the PON Media Access Control (MAC) layer and regarding the acquired time as the time the first clock packet is sent; and sending a second clock packet in a second downstream frame, where the second clock packet carries the time the first clock packet is sent.

Abstract: A method is provided for detecting scrambling of a radiocommunication network. The method is applied by a radiocommunication circuit capable of being connected to the network by being synchronized on a radiocommunication channel. The method includes a final detection phase, having the following steps: detection of verification of the following final condition: there are N radiocommunication channels on which the radiocommunication circuit cannot be synchronized despite detection of a power level normally sufficient for being synchronized, where N>2; and if the final condition is verified, generation of a final scrambling signal with a probability of scrambling equal to 100%. The method also includes at least one intermediate detection phase, having the following steps: detection of verification of at least one intermediate condition; and if the at least one intermediate condition is verified, generation of an intermediate scrambling signal with a probability of scrambling of less than 100%.

Abstract: A general-purpose, low-cost system provides comprehensive physiological data collection, with extensive data object oriented programmability and configurability for a variety of medical as well as other analog data collection applications. In a preferred embodiment, programmable input signal acquisition and processing circuits are used so that virtually any analog and/or medical signal can be digitized from a common point of contact to a plurality of sensors. A general-purpose data routing and encapsulation architecture supports input tagging and standardized routing through modern packet switch networks, including the Internet; from one of multiple points of origin or patients, to one or multiple points of data analysis for physician review. The preferred architecture further supports multiple-site data buffering for redundancy and reliability, and real-time data collection, routing, and viewing (or slower than real-time processes when communications infrastructure is slower than the data collection rate).

Abstract: The disclosure aims to implement an automatic frequency offset compensation of the frequency between emitter and receiver equipments, in radio frequency modules, with a frequency offset that can be larger than that the receiver can allow, without time loss and extra consumption. To solve this problem, the disclosure provides an automatic frequency offset compensation device comprising a reception front end, at least a filter, an I/Q demodulator for obtaining the I (In Phase) and Q (Quadrature) parameter, an automatic frequency control AFC unit for comparison of a received frequency with the real frequency of the equipment, and a microcontroller and a frequency synthesizer. In this device, the frequency offset is calculated by the AFC unit from the information given by the I/Q demodulator.

Abstract: Apparatus and methods are disclosed, such as those involving deskewing serial data transmissions. One such apparatus includes a plurality of receivers, each of which is configured to receive a serial data stream. Each of the receivers includes a shift register including a plurality of stages arranged in sequence to propagate a stream of characters. Each of the stages is configured to store a character, and shift the character to a next stage in response to a clock signal. The receiver also includes a multiplexer having a plurality of inputs, each of the inputs being electrically coupled to a respective one of the stages of the shift register, and to select one of the stages to generate an output such that the outputs of the multiplexers in the receivers are deskewed.

Abstract: Apparatus and methods are disclosed, such as those involving deskewing serial data transmissions. One such apparatus includes a plurality of receivers, each of which is configured to receive a serial data stream. Each of the receivers includes a shift register including a plurality of stages arranged in sequence to propagate a stream of characters. Each of the stages is configured to store a character, and shift the character to a next stage in response to a clock signal. The receiver also includes a multiplexer having a plurality of inputs, each of the inputs being electrically coupled to a respective one of the stages of the shift register, and to select one of the stages to generate an output such that the outputs of the multiplexers in the receivers are deskewed.

Abstract: Methods and apparatus are provided for pseudo asynchronous testing of receive paths in serializer/deserializer (SerDes) devices. A SerDes device is tested by applying a source of serial data to a receive path of the SerDes device during a test mode. The receive path substantially aligns to incoming data using a bit clock. A phase is adjusted during the test mode of the bit clock relative to the source of serial data to evaluate the SerDes device. The source of serial data may be, for example, a reference clock used by a phase locked loop to generate the bit clock. The phase of the bit clock can be directly controlled during the test mode, for example, by a test phase control signal, such as a plurality of interpolation codes that are applied to an interpolator that alters a phase of the bit clock.