Abstract: A universal series bus (USB) frequency synchronous apparatus using a start of frame (SOF) signal generated by a master device to mark a reference interval is disclosed. The frequency synchronizing apparatus includes a frequency divider, a counter unit with a default pulse number, an arithmetic unit, and an adjusting unit. The frequency divider divides a high frequency signal by a variable frequency factor to generate a lock frequency signal. The counter is used to detect a pulse number of the lock frequency signal at a reference interval and obtain a pulse difference between the default pulse number and the detected pulse number of the lock frequency signal.

Abstract: A modem unit inputs a plurality of combinations, of control signal and data signal, which are to use a plurality of subcarriers. In a plurality of combinations the modem unit adds a first known signal for data signals contained at least in a first combination, and in a plurality of combinations inputted to an input unit it adds second known signals for a second combination and the subsequent combinations, respectively, in anterior positions. The modem unit uses part of a plurality of subcarriers for control signals contained respectively in the second combination and the subsequent combinations, and defines a second known signal in a manner that a part corresponding to the part of a plurality of subcarriers is extracted from the first known signal.

Abstract: Provided is a method of generating a pilot pattern capable of perform adaptive channel estimation, and a method and apparatus of a base station and a method and apparatus of a terminal using the pilot pattern. The pilot pattern selects pilot symbol positions based on distances from pilots of previous orthogonal frequency division multiple access (OFDMA) symbols to a subcarrier position of a current OFDMA symbol in the frequency domain and the time domain, so that a low pilot density is maintained so as to effectively transmit data, and stable channel estimation performance can be obtained even in a bad channel environment. In addition, the minimum burst allocation size is determined according to the channel environment between the base station and the terminal, guaranteeing channel estimation performance suitable for the channel environment, and improving granularity, channel estimation latency, and channel estimation memory size.

Abstract: Disclosed are an apparatus and a method for controlling ranging in a wireless communication system. The apparatus according to the present invention comprises a Radio Frequency (RF) module converting RF band signals received via antenna to low-frequency band signal; a Fast Fourier Transform (FFT) module converting the low-frequency band signal of time-domain to frequency-domain signal; a derandomizer performing derandomizing the frequency-domain signals by using a random sequence being transmitted by the terminals; a depermutation module combining the frequency-domain signals output from the derandomizer by unit of burst and outputting the combined signal; and a ranging controller controlling periodic ranging of the terminal corresponding to the respective bursts by estimating phase change in the frequency-domain signals of burst unit.

Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot. symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.

Abstract: In one non-limiting aspect thereof, the exemplary embodiments of this invention provide a user equipment that includes a data processor; and a wireless transceiver configured to transmit uplink pilot signals during sub-bands and slots, wherein at least three blocks (LB1, LB2 and LB3) are reserved for pilot signals. LB1 and LB2 include in-band pilot signals transmitted using a dedicated pilot code. The wireless transceiver is further configured to transmit LB3 using a frequency hopping pattern and pilot code allocation that are based on a slot and a sub-band in which a first LB3 is transmitted. Thus, the code and hopping pattern of a scheduled user equipment are resource-specific (defined by an allocated resource), as opposed to being user equipment-specific.

Abstract: The present invention discloses a method for inserting a downlink common pilot in a TDD system and more particularly to a method for inserting a downlink common pilot in a TDD system based on OFDMA technology and the method includes two steps. A: data to be transmitted are divided into several segments to be transmitted in several continuous time periods, wherein each time period includes several slots with at least one downlink slot; B: a common pilot is inserted in one downlink slot in the time period. Therefore, the scheduling based on the frequency domain can be achieved by measuring the common pilot channel.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: A communication system to feed remote antenna nodes with simulcast traffic and non-simulcast beacons is provided. The communication system includes a host radio frequency (RF) digitizer, a delay buffer, a summing circuit, and a framer/serializer. The host RF digitizer receives CDMA base station signals for simulcast CDMA-traffic-bearing channels and to output digital samples. The delay buffer is communicatively coupled to receive the samples output from a beacon pilot generator and to output digitally delayed CDMA-digital-beacon-pilot samples having different pseudo-noise offsets. The summing circuit adds the CDMA-digital-beacon-pilot samples having different pseudo-noise offsets to the digital samples received from the host RF digitizer to form composite simulcast-plus-uniquely-offset-beacon-pilot CDMA samples.

Abstract: Methods and apparatus for time tracking using assistance from TDM pilots in a communication network. In an aspect, a method is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The method includes determining a delay spread, and modifying at least one parameter used by the time tracking algorithm based on the delay spread. In another aspect, an apparatus is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The apparatus includes computation logic for determining a delay spread, and control logic for modifying at least one parameter used by the time tracking algorithm based on the delay spread.

Abstract: In a wireless mobile communications system, a method for processing paging information allows the operations of a mobile terminal to be simplified and permits efficient use of resources for the mobile terminal. The network instructs in advance, the transmission of control information, such as a particular paging message, a notification message, system information and the like, via a single indicator channel. The mobile terminal receives this single indicator channel and uses the indicator information that was transmitted via the indicator channel in order to receive the control information.

Abstract: The present disclosure provides a method and apparatus of channel estimation for a wireless communication system. Dedicated pilot symbols transmitted over at least one time-frequency region for at least one user are received. Channel parameters are estimated for the at least one time-frequency region based on the received dedicated pilot symbols.

Abstract: Disclosed are a channel estimation method and a channel estimation apparatus, and a receiver using the same. The channel estimation apparatus provided in the receiver detects pilot signals from radio signals and estimates channels of the detected pilot signals. The channel estimation apparatus estimates channels corresponding to data by conducting linear interpolation, which allows for simultaneous interpolation in time and frequency axes, by use of information on the estimated pilot channels. Thus, the memory capacity required for the receiver can be reduced using channel estimation in which the simultaneous interpolation is conducted. Also, the performance of the receiver can be further improved in a wireless environment where the receiver moves at high speed.

Abstract: The invention concerns a method of transmitting, via a sending device, a data stream made up of data packets, at least some of these packets including time references for synchronizing the clocks of the sender and the receiver. The method includes at least a correction of the time references by the sender so as the receiver can offset the jitter introduced by the transmission. The invention is used to offset these losses of accuracy. The invention concerns also the device and corresponding receiver and reception method.

Abstract: Disclosed is a downlink signal configuring method and device, and synchronization and cell search method and device using the same in a mobile communication system. A downlink frame has plural symbols into which pilot subcarriers are distributively arranged with respect to time and frequency axes. Initial symbol synchronization and initial frequency synchronization are estimated by using a position at which autocorrelation of a cyclic prefix of a downlink signal and a valid symbol of the downlink is maximized, and cell search and integer-times frequency synchronization are estimated by using pilot subcarriers included in the estimated symbol. Fine symbol synchronization, fine frequency synchronization, and downlink frame synchronization is estimated by using an estimated cell search result.

Abstract: Systems and techniques are disclosed wherein a gated pilot signal can be re-acquired faster by searching a last known pilot offset and/or searching a last coset in which the last pilot signal was found.

Abstract: Mobile handheld terminals receiving DVB transmission require relatively low power consumption and TDM based transmission can be used to reduce power of the terminals. In order find pilot carrier position at least two symbols are accessed which are adapted to establish a correspondence pattern for pilot carriers in a matrix of the at least two symbols. Carriers of the first symbol are correlated with the corresponding carriers of the second symbol within the matrix for determining a correlation maximum for indicating a pilot carrier position.

Abstract: A digital broadcasting transmission/reception system having an improved receiving performance and a signal processing method thereof. The transmission system includes a FEC encoder encoding an incoming signal according to a certain FEC scheme, a sync insertion unit inserting a sync into the encoded signal, a hidden pilot insertion unit inserting a hidden pilot into the sync-inserted signal, a pilot insertion unit inserting a pilot tone into the hidden-pilot-inserted signal, a pulse shaping filter pulse-shaping the pilot-tone-inserted signal with a certain roll-off factor, and a RF unit transmitting the pulse-shaped signal through a transmission channel band. Performances of equalization and synchronization acquirement can be enhanced in multipath conditions by utilizing the transmission system containing the hidden pilot.

Abstract: An apparatus and method for transmitting/receiving control information using a pilot pattern inserted in a plot field of a dedicated physical channel in a mobile communication system including a transmitter for transmitting data and a receiver for receiving the data. The apparatus and method include selecting control information according to whether the data is received; and selecting a pilot pattern according to the control information, and inserting the selected pilot pattern in a pilot field of a dedicated physical channel as the control information, before transmission. The pilot pattern includes a first pilot pattern used when the control information is not transmitted, a second pilot pattern being orthogonal with the first pilot pattern, and a third pilot pattern generated by inverting a sign of the second pilot pattern.

Abstract: Systems and methods for performing a handoff of an access terminal from a macro node to a femto node are disclosed. To direct handoff of the access terminal, an identity of the femto node is determined A femto node provided may be indentified by at least a difference between the offset of a first pilot signal and the offset of a second pilot signal.

Abstract: At a base station apparatus, known pilot signals for use in channel estimation are transmitted, and in addition thereto MCS pilot signals that are used to perform adaptive modulations respectively corresponding to a plurality of modulation schemes are multiplexed and output. A mobile station apparatus dispreads the respective MCS signals out of the multiplex signal, compares these to known symbols patterns, and sends the MCS pilot signals that show a matching relationship to the base station apparatus as a mobile station reception result. Upon receiving the mobile station reception result from the mobile station apparatus, the base station apparatus selects the modulation scheme of the optimum modulation level for the downlink signals. This configuration makes it possible to switch the modulation schemes in an accurate and simple way.

Abstract: A method is described for establishing one user from multiple users of a data network as a pilot master for emitting a pilot signal, to which the other users of the data network may synchronize themselves. In the related art, a pilot signal is typically generated by a separate pilot signal generator or a permanently predefined selected user. However, this has the disadvantage that if the pilot signal generator or the selected user malfunctions, synchronization and therefore also communication of the users with one another via the data network is no longer possible. In order to avoid this disadvantage, it is suggested that at least two of the users of the data network be implemented to be pilot-master-capable and one of them assume the pilot mastership according to a described method.

Abstract: A system, method and apparatus includes a transmitter that has an encoder and baseband modulator that encodes and modulates a sequence of payload data symbols as a signal constellation to be communicated. An amble generator and baseband modulator generates amble symbols as a known sequence of M symbol times in length every N symbol times. A multiplexer multiplexes the data and amble symbols together to form a communications signal that is transmitted over a communications channel.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: A wireless communications device which may include a wireless receiver for receiving wireless signals comprising unknown data portions over a channel, and a demodulator connected to the wireless receiver. The demodulator may be for estimating a delay spread and a fade rate associated with the channel, determining a desired time-domain interpolation filter based upon the estimated fade rate, and determining a desired frequency-domain interpolation filter based upon the estimated delay spread. The demodulator may further generate channel estimates for the unknown data portions based upon the desired time-domain interpolation filter and the desired frequency-domain interpolation filter, and determine the unknown data portions based upon the channel estimates.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: A base station (BS), a subordinated station (SS) and the transmission methods thereof for use in a multi-input multi-output (MIMO) network are provided. The BS stores resource allocation information about the MIMO network and an SS list, and generate a super frame according to the resource allocation information and the SS list. The super frame comprises a pilot pattern which comprises a plurality of pilots and data. The BS and SS both considers the pilot pattern as an identifier of the SS. When there are communications occurred between the BS and the SS, the BS/SS will confirm whether the pilot pattern of the super frame matches the identifier of the SS to reduce interference from other stations in the MIMO network.

Abstract: A method and apparatus for performing codebook-based precoding in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. In a method for operating a Base Station (BS) in a MIMO wireless communication system, a reference signal including pilot signals, which are divided by a predefined number of bands and are multiplied by respective codes in a codebook, is transmitted. One or more Mobile Stations (MSs) destined for spatial multiple access are selected using an index of a band and CQI of the band corresponding to the index, which are fed back from one or more MSs. A precoding matrix is generated to process data streams of the selected one or more MSs.

Abstract: In OFDMA wireless communications systems, pilot pattern design is optimized based on predefined resource block size. The number of pilots and the spacing between pilots within a resource block is determined based on a set of system requirements. In one novel aspect, pilots are allocated within a resource block to avoid channel extrapolation in both frequency domain and time domain. First, four pilots are positioned at four corners of the resource block. Next, the remaining pilots are maximally evenly distributed within the resource block along both the frequency domain and the time domain. Finally, it is verified that an approximately equal number of pilots are evenly distributed along the time domain with respect to each data stream to minimize power fluctuation. For uplink transmission, one or more frequency tones at one or more edges of the resource block are reserved to be pilot-free to reduce multiuser synchronization error effect.

Abstract: In OFDMA wireless communications systems, pilot pattern design is optimized based on predefined resource block size. The number of pilots and the spacing between pilots within a resource block is determined based on a set of system requirements. In one novel aspect, if resource block size is smaller than three in either frequency or time domain, then the pilots are allocated such that average pilot-to-data distance is minimized and that pilot-to-pilot distance is as large as possible. In one example, m pilots are allocated in an i×j resource block. The resource block is partitioned into n equal sub blocks, where m is a multiple of n. Within each sub block, m/n pilots are positioned such that average pilot-to-data distance is minimized. On the other hand, if resource block size is larger than or equal to three in both frequency and time domain, then pilots are allocated to avoid channel extrapolation.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: Systems and techniques are disclosed detecting an embedded signal which includes producing a plurality of first correlated values from a portion of the first signal and a second signal, transforming the first correlation values into a plurality of second correlation values related to a frequency content of the first correlation values, and searching for the embedded signal by evaluating the second correlation values. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A predetermined network packet is utilized for power reduction in either or both of a transmitter and receiver when information is not needed. Upon detection of the predetermined network packet type, various portions of the transmitter and/or receiver may be clock gated or powered down.

Abstract: In case of disposing a pilot symbol in data transmission which depends on a DWMC transmission system, in a plurality of transmission symbols on a time axis, a pilot symbol, which becomes a signal of a sine wave, is configured, by giving contiguous identical data in a plurality of predetermined symbols. By transmitting a transmission signal with the use of this pilot signal, between a transmitting device and a receiving device, it is possible to carry out channel equalization by complex information which is obtained from a pilot symbol.

Abstract: The present invention provides an audio data sync format detecting circuit that can minimize both the hardware configuration software processing, and furthermore, has a large flexibility with respect to unknown formats. Audio data is written in sequence into a data register, where the audio data are units having a predetermined number of bits. Samples of the format that is the object of detection are written in sequence into a register. A comparator compares the data in the sample register and the data in the data register. A control circuit receives hit signals and outputs an interrupt signal to the controller, and the controller writes in sequence samples of the format that is the object of detection into the register each time an interrupt signal is received. When hit signal is continuously output a predetermined number of times, a match detection circuit outputs a format match signal.

Abstract: In an OFDM system the same Walsh code is used at the same time for a plurality of transmitters. The multiple transmitters can be from the same, or different devices (e.g., different base stations on the downlink, different terminals on the uplink). Each subcarrier/antenna combination will share a similar pilot Walsh code, except for the fact that the scrambled spread pilot signals will be phase shifted on some subcarriers of some antennas, based on the subcarrier/antenna combination.

Abstract: In case of disposing a pilot symbol in data transmission which depends on a DWMC transmission system, in a plurality of transmission symbols on a time axis, a pilot symbol, which becomes a signal of a sine wave, is configured, by giving contiguous identical data in a plurality of predetermined symbols. By transmitting a transmission signal with the use of this pilot signal, between a transmitting device and a receiving device, it is possible to carry out channel equalization by complex information which is obtained from a pilot symbol.

Abstract: A mobile channel estimation algorithm is disclosed, for use in a DVB-H coded OFDM demodulator. The mobile channel estimation algorithm estimates the mobile channel transfer function, overcoming many of the delay spread limitations without using time filtering and without having to collect many OFDM symbols. Once the channel estimate has been found for each symbol, equalization and inter-carrier-interference cancellation may be carried out relatively easily using known methods. The mobile channel estimation algorithm may be used in DVB-H as well as in other areas of OFDM.

Abstract: A method for handling a Timer_Status_Periodic timer in a wireless communications system includes starting the Timer_Status_Periodic timer for a Radio Link Control Acknowledged Mode (RLC AM) entity, performing a re-establishment procedure for the RLC AM entity, and not stopping the Timer_Status_Periodic timer after re-establishment of the RLC AM entity.

Abstract: A method is disclosed that includes measuring, during a measurement period, values corresponding to noise and interference signals received from a channel. The measurement period coincides with a period when no signal is transmitted on the channel. The method also includes determining one or more thresholds based upon the measured values. Second signals that correspond to a message are received on the channel. The message includes an indicator having a number of possible states. A value is determined corresponding to the indicator based upon the second signals. One of the possible states is assigned to the indicator of the received message based upon the one or more thresholds and the determined value.

Abstract: A technique for efficient implementation of pilot signals on a reverse link in a wireless communication system. An access channel is defined for the reverse link such that within each frame, or epoch, a portion is dedicated to sending only pilot symbols. Another portion of the frame is reserved for sending mostly data symbols; however, within this second portion of the frame, additional pilot symbols are interleaved among the data symbols. The pilot symbol or preamble portion of the access channel frame allows for efficient acquisition of the access signal at the base station, while providing a timing reference for determining the effects of multipath fading. In particular, a pilot correlation filter provides a phase estimate from the pilot symbols in the preamble portion, which is then used to decode the data symbols in the payload portion. An access acquisition portion of the receiver uses the phase estimates provided by the pilot correlation filter to process the output of a data symbol correlation filter.

Abstract: Techniques for sending sector/system information in TDM pilots using a hierarchical pilot structure are described. A base station sends multiple sets of bits for the sector/system information in multiple TDM pilots. The set of bits sent in a given TDM pilot may include bits sent in earlier TDM pilots. In one design, the base station generates a first TDM pilot based on a first set of bits, generates a second TDM pilot based on a second set of bits that includes the first set, generates a third TDM pilot based on all bits for the information, and sends the TDM pilots. A terminal performs detection to obtain a first detected value for the first TDM pilot, performs detection based on the first detected value to obtain a second detected value for the second TDM pilot, and performs detection based on the first and second detected values to obtain a third detected value for the third TDM pilot.

Abstract: A method for compensating IQ imbalance is disclosed. First, an OFDM signal is received. The OFDM signal is translated into frequency domain, wherein the translated OFDM signal has N sub-carriers noted as Y(1)-Y(N). The IQ imbalance compensation factor is generated according to the k-th sub-carrier of the translated signal Y(k), the (N?k+2)-th sub-carrier of the translated signal Y(N?k+2), and the complex conjugates thereof.

Abstract: Method and apparatus for OFDM synchronization and channel estimation. In a temporal embodiment, received embedded system pilot symbols are inverse Fourier transformed at expected index locations and correlated with computed complex conjugates of inverse Fourier transforms of pilot symbols for providing a correlation function for the channel impulse response. In a frequency domain embodiment, embedded system pilot symbols are augmented with pilot-spaced inferred guard band symbols, multiplied by scaled complex conjugates of computed pilot systems, and inverse Fourier transformed into the channel impulse response. Time and frequency are synchronized in feedback loops from information in the channel impulse response. The channel impulse response is filtered, interpolated, and then Fourier transformed for determining channel estimates for equalization.

Abstract: A system, method and apparatus includes a transmitter that has an encoder and baseband modulator that encodes and modulates a sequence of payload data symbols as a signal constellation to be communicated. An amble generator and baseband modulator generates amble symbols as a known sequence of M symbol times in length every N symbol times. A multiplexer multiplexes the data and amble symbols together to form a communications signal that is transmitted over a communications channel.

Abstract: A method and apparatus are provided for the transmission of radio data between at least two transmitters and one receiver, said method employing at least one multi-carrier data transmission signal. The aforementioned multi-carrier signal is formed by a temporal succession of symbols comprising: (i) informative data elements, and (ii) reference elements known as pilots which are distributed within the informative data elements according to a pre-determined pattern. Moreover, the value of said pilots at transmission is known to the receiver. At least two transmitters use different pilot patterns such that, at a give instant and a give frequency, only one pilot can be received (possibly with other informative data elements) by the receiver from other transmitters.

Abstract: A method is provided for extracting a sequence of pilot symbols enabling to estimate the transfer function of a transmission channel. At least a radiocommunication device communicates through the channel with a remote station, the latter regularly delivering to the radiocommunication device a reference pattern. The structure of the reference pattern is variable, depending on at least one characteristic of the transmission channel.

Abstract: Systems and techniques are disclosed wherein a gated pilot signal can be acquired by producing a plurality of product values for each of a first and second signal and a generated signal, coherently combining portions of the product values produced from the first signal and noncoherently combining those coherently combined portions to produce a first value, coherently combining portions of the product values produced from the second signal and noncoherently combining those coherently combined portions to produce a second value, and noncoherently combining the first and second values.

Abstract: There is provided a method and apparatus for selecting an appropriate base station and an optimal data rate to provide a voice service and a data service based on a voice service load in a CDMA system. A base station transmits two pilot signals orthogonally spread with different orthogonal codes in association with its voice service load, and a mobile station estimates the voice service load based on a pilot power ratio.

Abstract: By providing a interference power estimation unit obtaining the power of interference in a common pilot signal with ten symbols in one slot and outputting the power of interference as the estimate of the amount of interference in the data signal's pilot signal and a signal-to-interference power ratio calculation unit calculating a signal-to-interference power ratio (SIR) using an output of the interference power estimation unit, in a spread spectrum communication method, a correct SIR can be estimated even when the number of symbols of an individual pilot signal in the slot of the data channel is small.