Abstract: A receiver for determining sample phase comprises a sync detector to output a sample phase; an interpolator communicatively coupled to the sync detector and to generate a plurality of interpolated phases, wherein each of the interpolated phase and phases within the phase set corresponds to a respective syncword; a calculator communicatively coupled to the interpolator to calculate an error vector magnitude (EVM) of syncword corresponding respectively to each of the interpolated phase and to each of the phase within a phase set, and determine the minimum EVM among EVMs for the syncword corresponding to each of the interpolated phase and the EVM of syncword corresponding to each of the phase within the phase set; and an output unit communicatively coupled to the calculator and configured to sample and output payload signals at the phase corresponding to the minimum EVM.

Abstract: A method includes receiving a first plurality of symbols comprising complex portions. The method further includes applying conjugate symmetry to the first plurality of symbols, producing a second plurality of symbols comprising no complex portions. The method further includes transforming the second plurality of symbols using an inverse fast Fourier transform, producing a third plurality of symbols. The method further includes interpolating the third plurality of symbols, generating a short training field comprising at least one real portion of the third plurality of symbols, generating a long training field comprising at least one real portion of the third plurality of symbols, and transmitting the short training field and long training field in a WPAN.

Abstract: A transmission apparatus includes a symbol arrangement unit to receive multiple symbols constituting a block, duplicate a first symbol of a block one block previous to the block, and output a block symbol being the present block with the duplicated duplicate symbol inserted at a first position thereof, a frequency conversion unit to convert the block symbol into a frequency domain signal, a frequency component removal unit to remove one or more frequency components from the frequency domain signal, a time conversion unit to convert, after interpolation on the frequency domain signal with the frequency components removed, the interpolated frequency domain signal into a time domain signal, and a cyclic prefix insertion unit to duplicate, in the time domain signal, a signal from a position based on the first position through an end as a cyclic prefix, and insert the cyclic prefix at a beginning of the time domain signal.

Abstract: A method for performing high speed mode detection of a carrier frequency offset (CFO) includes receiving a Zadoff-Chu signal at a wireless device, and determining a plurality of correlation peaks based on a correlation of the signal with one or more known Zadoff-Chu sequences. The method includes determining a carrier frequency offset (CFO) associated with the signal based on a phases associated with the plurality of correlation peaks and a coarse CFO estimate. The coarse CFO estimate may be determined based on a squared power ratio of particular pairs of the plurality of correlation peaks and the phases may be used to remove ambiguity associated with the coarse CFO estimate.

Abstract: Provided is an apparatus and method for transmitting data over a communication channel having at least one physical lane for transmitting data. The apparatus includes, for each physical lane, allocation circuitry configured for allocating data in logical lanes corresponding to the physical lane. The apparatus also includes, for each physical lane, a multiplexer configured for bit-interleaving the data from the logical lanes corresponding to the physical lane into interleaved data for transmission over the physical lane. In accordance with an embodiment of the present disclosure, for each physical lane, the allocation circuitry is configured for allocating the data such that the interleaved data for transmission over the physical lane has clusters of sequential bits of the same symbol. Thus, upon transmission and reception by a receiver, any correlated errors affecting sequential bits may affect fewer symbols. Also provided is an apparatus and method for receiving data in a complementary manner.

Abstract: A receiver that receives a reference symbol comprising a sequence of a plurality of synchronization repetition patterns, wherein each repetition pattern contains a predetermined number of samples. The reference symbol is part of a digital signal modulated by using OFDM modulation. An end synchronization repetition pattern in the reference symbol is phase-shifted by 180°, and the phase-shifted synchronization repetition pattern is positioned after the sequence of the number of synchronization repetition patterns. The receiver detects a timing of a correlation peak at the end of said reference symbol by performing a cross-correlation of the synchronization repetition patterns.

Abstract: A receiver that receives a reference symbol comprising a sequence of a plurality of synchronization repetition patterns, wherein each repetition pattern contains a predetermined number of samples. The reference symbol is part of a digital signal modulated by using OFDM modulation. An end synchronization repetition pattern in the reference symbol is phase-shifted by 180°, and the phase-shifted synchronization repetition pattern is positioned after the sequence of the number of synchronization repetition patterns. The receiver detects a timing of a correlation peak at the end of said reference symbol by performing a cross-correlation of the synchronization repetition patterns.

Abstract: A method for real-time data transmission in a communication network for transmitting useful data from a transmitter to a plurality of receivers, wherein the receivers are synchronized in terms of time via a synchronization method, at least one time for transmitting a respective useful data message to the receivers is stipulated during real-time data transmission, each of the receivers is assigned its own receiver useful data area within the useful data message, which area is assigned to the receiver, and the transmitter transmitting a useful data message. In accordance with the invention, a first of the receivers receiving this useful data message, stores the useful data contained in the receiver useful data area assigned to it for further processing, and forwards the useful data message to a second of the receivers at the transmission time.

Abstract: Embodiments describe synchronizing access routers with wireless terminal state information. According to an embodiment is a wireless terminal that transmits a message that includes an address for at least two access routers. State change information can optionally be included in the message. According to another embodiment is an access router that receives a state change notification from a wireless device or another access router. The state change notification is updated in the access router. An acknowledgment confirming the updated state change may be sent to the wireless terminal. Dynamic state synchronization is provided with minimal communication with wireless terminal.

Abstract: A method for wirelessly transmitting data using a plurality of transmission layers includes estimating a number of data vector symbols to be allocated to one or more user data codewords during the subframe and determining a number of bits in the one or more user data codewords. The method also includes calculating a nominal number of control vector symbols to allocate to control information based, at least in part, on the estimated number of data vector symbols and the determined number of bits in the one or more user data codewords. Additionally, the method includes determining an offset value based, at least in part, on a number of layers over which the wireless terminal will be transmitting during the subframe and calculating a final number of control vector symbols by multiplying the nominal number of control vector symbols and the offset value.

Abstract: Aspects of the disclosure provide a method that includes receiving a first packet through a network at a first device. The first packet includes a first message generated according to a precision time protocol and a first encapsulation that encapsulates one or more fields of the first message. Further, the method includes security-verifying the first packet based on the first message and the first encapsulation, and processing the first message according to the precision time protocol after the first packet is security-verified.

Abstract: Under a wireless communication environment in which nodes sharing a time reference communicate information with a frame having a predetermined structure, when a node that has failed to acquire synchronization, a protocol in which neighboring nodes relays synchronization to the synchronization acquisition failed node by using a preamble defined in the frame is provided.

Abstract: Two or more data packets transmitted through a wireless channel are received using a receiver device. The two or more data packets are a result of two or more transmissions that are made sequentially in time at different center frequencies in order to span a desired bandwidth. Each data packet of the two or more data packets is transmitted at a single center frequency. Time differences and/or carrier phase differences among the two or more transmissions are estimated. A time-of-arrival of one or more data packets of the two or more data packets is calculated using each data packet of the two or more data packets and one or more of the estimated time differences, the different center frequencies, and the estimated carrier phase differences.

Abstract: System and methods for synchronizing real time networks. Systems may include a first device located on a first real time network that may include a functional unit, a port, and a plurality of output queues configured for segregation of network packets based on a mapping of one or more additional real time networks to respective output queues. For each of the one or more additional real time networks, synchronization packets may be generated based on a master clock. The packets may be usable by a network timekeeper of the additional real time network to synchronize the additional real time network to the master clock. The synchronization packets may be stored in a respective output queue based on the mapping and may be sent to the network timekeeper of the additional real time network via the port.

Abstract: Systems and methods for synchronizing clocks across networks using a time-sensitive (TS) network interface controller (NIC). The TS NIC may include a functional unit, a port, a clock, a plurality of input/output queue pairs, and a time stamp unit (TSU). The functional unit may be configured to generate synchronization packets usable by an NTS network timekeeper of a respective NTS network to synchronize the NTS network to the master clock, including using the TSU to generate time stamps for the synchronization packets in accordance with the clock synchronized to the master clock and communicate with the respective NTS network via the port using the corresponding input/output queue pair, including sending the synchronization packets to the NTS network timekeeper of the respective NTS network.

Abstract: Applications executed out of router memory may acquire additional bandwidth that is not being used by other applications, in order to speed up network traffic. Scavenging may occur up to a point where current congestion is detected, at which point any scavenged bandwidth is relinquished and the application returns to its prescribed limit. After current congestion is mitigated, scavenging may occur up to a limit below the point where congestion was detected. After a predetermined interval, additional scavenging may occur beyond this limit until a preset bandwidth limit is reached.

Abstract: Disclosed is a spectrum spread communication system which is hardly influenced by noises, and in which a frame structure can be identified at a receiving side without use of a frame synchronization signal. A spread code generator switches spread codes (“Scai” and “Scbi”) in each frame, and outputs it to a spread modulation unit. The spread modulation unit performs spread modulation of transmission data, and transmits it to a direct current power line. A reference code generator generates reference codes (“Scai” and “Scbi”) in the same code phase. Spread demodulation units performs spread demodulation of the received signal with use of the reference codes (“Scai” and “Scbi”), and output it to a selection unit. A frame synchronization detection unit identifies a frame structure on the basis of switching of a synchronization state of a code phase in a code phase synchronization detection unit.

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 self-synchronous scrambler/descrambler and method for operating same are disclosed. A self-synchronous scrambler/descrambler comprises an M-bit Scrambler State memory for retaining M previously scrambled/descrambled bits, a SOP/EOP Zero Inserter for receiving replacing certain bytes of the bus word with a value of zero, a Mid-Packet Word Logic for scrambling/descrambling the received bits using the previously scrambled/descrambled bits from the M-bit Scrambler State memory; and a Barrel Shifter for rotating the M-bit Scrambler State memory backwards. The method for scrambling/descrambling bits, comprising receiving a bus word, replacing certain bytes of the bus word, scrambling/descrambling bits of the bus word by exclusive-ORing with previously scrambled/descrambled bits, retaining the scrambled/descrambled bits of the bus word; and rotating the scrambled/descrambled bits of the bus word backwards an amount.

Abstract: A system and method for timing synchronization between network nodes. The timing synchronization can conform to the Precision Time Protocol (PTP) as defined in the IEEE 1588 protocol. The timing synchronization can include the insertion of ingress and/or egress timestamps into packets. For example, timestamps can be inserted into reserved fields of the header of a packet. The timing synchronization can also include the utilization of one or more reserved fields to initiate the generation of a timestamp upon the transmission of the packet and/or the retrieval of a previously stored timestamp.

Abstract: Systems and methodologies are described that facilitate scrambling of downlink reference signals utilizing a pseudo-random sequence (PRS) corresponding to a primary synchronization code (PSC) and secondary synchronization code (SSC) combination. Utilization of the combination allows for orthogonal sequencing to be removed from the scrambling. This can be beneficial, for example, where resources required for orthogonalizing the reference signal outweigh the benefit of utilizing the orthogonal sequences. In such scenarios, selective scrambling can be utilized such that the orthogonal sequence or instead the PSC/SSC combination can be provided to leverage advantages of both mechanisms in the given scenarios.

Abstract: In one embodiment, a battery-operated communication device “quick-samples” a frequency hopping sequence at a periodic rate corresponding to a substantially low duty cycle, and is discovered by (e.g., attached to) a main-powered communication device. During a scheduled sample, the main-powered communication device transmits a control packet to be received by the battery-operated communication device, the control packet containing timing information and transmitted to account for worst-case clock drift error between the two devices. The battery-operated communication device responds to the control packet with a link-layer acknowledgment containing timing information from the battery-operated communication device. Accordingly, the two devices may re-synchronize their timing based on the timing information in the control packet and acknowledgment, respectively.

Abstract: A transparent clock may be provided between edge nodes of a non-precision time protocol network, with an arrival time of a packet at an edge of the non-precision time protocol network carried in a reserved field of a packet.

Abstract: Disclosed herein is a reception apparatus, including: a reception section configured to receive an OFDM (orthogonal frequency division multiplexed) signal obtained by modulating a common packet sequence configured from a packet common to a plurality of streams and a data packet sequence configured from packets individually unique to the plural streams; a buffer configured to accumulate packets of the common packet sequence and the data packet sequence obtained by demodulating the received OFDM signal; a retaining section configured to retain correction information for correcting out-of-synchronism between the common packet sequence and the data packet sequence obtained from particular packets of the common packet sequence and the data packet sequence upon reading out of the packets accumulated in the buffer; and a correction section configured to correct the out-of-synchronism of the packet which suffers from the out-of-synchronism of the packets based on the correction information retained in the retaining s

Abstract: A method for signaling a time and/or clock through a header station generating a transport datastream from video and/or audio data to at least one receiver of the transport datastream calculates the time information (PCRN+1; RTPN+1; TN+1) integrated in a transport data packet of the transport datastream iteratively from the time information (PCRN; RTPN; T1) of the transport data packet last transmitted in the transport datastream with integrated time information, from a transmission time of data bits transmitted since the last transmitted transport data packet with integrated time information in the transport datastream and from a clock (fPCR; fSys). The time information (PCRN+1, PCRN; RTPN+1, RTPN; TN+1, T1) serves in each case for the signaling of times or a clock, and, in each case, contains a pulse number counted up to the transmission time of the respective transport data packet of the clock (fPCR; fSys).

Abstract: Provided are a synchronization acquisition method and apparatus in a multi-carrier system. A terminal acquires the synchronization for a first downlink component carrier by detecting a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) in the first downlink component carrier. The terminal acquires the synchronization for a second downlink component carrier by detecting a reference signal in the second downlink component carrier.

Abstract: A base station apparatus is provided, which includes a generator configured to generate a synchronization signal and a transmitter configured to transmit the generated synchronization signal. The generator is configured to generate a synchronization signal to be mapped on a subcarrier included in one of a plurality of frequency resource candidates that are separated by an interval, which is a common multiple of a determined frequency spacing and a subcarrier spacing between contiguous subcarriers, wherein the subcarrier spacing does not have a value that is a divisor of the determined frequency spacing.

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 network terminal has communication section that communicates with other network terminals connected via a network, time-series data creation section that, at timing set beforehand, creates time information including a correspondence between an identification number of the own network terminal and a current time measured by a timer of the own network terminal and creates time-series data registering the time information, and additional registration section that, when the communication section receives the time-series data transmitted from another network terminal, creates time information including a correspondence between the identification number of the own network terminal and a current time measured by the timer of the own network terminal and additionally registers the time information to the time-series data received this time.

Abstract: A radio communication network having at least two base stations. The base stations communicate with mobile stations using time slots. The time slots are divided into transmission slots, during which the base stations transmit messages, and receiving slots, during which the base stations receive messages. The base stations jointly determine an assignment of the time slots as transmission slots and receiving slots.

Abstract: A method and system of distributing clock synchronization information within an optical communications network including a plurality of network elements, in which a first network element receives an ingress clock synchronization message, the ingress clock synchronization message including a clock synchronization message identifier and a correction field. The first network element inserts the clock synchronization message identifier into an optical channel frame overhead and inserts the ingress clock synchronization message into an optical channel frame payload. The first network element transmits the optical channel frame overhead and the optical channel frame payload to a second network element, and determines a transit time of the clock synchronization message identifier across each of the network elements. The second network element updates the correction field of the ingress clock synchronization message with said transit times to form an egress clock synchronization message.

Abstract: Multiple control indications are transmitted within timeslots defined for a slotted communication system. For example, a wireless node may transmit a control indication at a beginning of a timeslot and at an end of a timeslot. A control indication may comprise a resource utilization message that a node generates in an attempt reduce inference at the node that is caused by transmissions by neighboring nodes. A node also may synchronize to a received timeslot of another node based on the position of one or more control indications within the timeslot. Here, each control indication may include information that indicates the position of the control indication within the timeslot.

Abstract: A transmission method of a femtocell includes the following steps. The femtocell receives and temporarily stores multiple real-time transport protocol (RTP) packets from a UE in a buffer. When the RTP packets are temporarily stored for a time period, the femtocell samples the buffer at a sampling rate to generate multiple CS data packets. The CS data packets include a current CS data packet. When there exists no previous CS data packet received from the UE, the femtocell calculates a timestamp of the current CS data packet according to a current timestamp. When there exists the previous CS data packet, the femtocell calculates the timestamp of the current CS data packet according to the timestamp and a connection frame number (CFN) of the previous CS data packet and a CFN of the current CS data packet.

Abstract: A system and method for transmitting and recovering external clock signals over links of a DSL system in which the external clock signals are used to synchronize transmitted physical layer signals from a CO of a DSL system and said external clock signals are derived from the received physical layer signals at an RT/CPE location of a DSL system. A clock recovery subsystem located at both the CO and the RT/CPE comprises a clock monitor circuit in communication with a Phase Lock Loop circuit. The clock monitor circuit at the RT/CPE is able to derive clock signals from the received physical layer signals and select one of said derived clocks to which a local reference clock at the RT/CPE is synchronized. The synchronized local reference clock, which can exist even when there are no valid derived clocks, may be used to transmit pseudowire frames (e.g., TDM data over Ethernet).

Abstract: A technique for encoding digital communication signals. Data symbols are augmented in pilot symbols inserted at predetermined positions. The pilot augmented sequence is then fed to a deterministic error correction block encoder, such as a turbo product coder, to output a coded sequence. The symbols in the error correction encoded sequence are then rearranged to ensure that the output symbols derived from input pilot symbols are located at regular, predetermined positions. As a result, channel encoding schemes can more easily be used which benefits from power of two length block sizes.

Abstract: An interface and corresponding method, where the interface is connected via a first connection to a factory data bus of a vehicle which transports signals according to a first data format, and further connected via a second connection to a data channel of the aftermarket component which transports signals according to a second data format. The interface identifies a factory data bus type corresponding to the factory data bus, out of a plurality of potential factory data bus types. The interface receives digital signals from the aftermarket component via the second connection, the digital signals being in the second data format which corresponds to the aftermarket component. The interface translates the digital signals into the first data format which corresponds to the identified factory bus type. The interface transmits the translated digital signals in the first data format to the vehicle via the first connection.

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: In one aspect, the method of synchronizing a communications device in a wireless communications network comprises receiving a beacon signal at a first frequency; and receiving a data signal at a second frequency, the beacon signal being used to synchronize reception of the data signal. In another aspect, the method comprises transmitting a beacon signal at a first frequency; and transmitting a data signal at a second frequency, the beacon signal being useable to synchronize reception of the data signal. The first frequency is substantially less than the second frequency such that the beacon signal experiences substantially different frequency-dependent propagation effects to the data signal.

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 method of synchronizing a plurality of data streams. A land mobile radio (LMR) data stream can be generated by a LMR communication device. At least one LMR identifier can be communicated from the LMR communication device to a broadband communication device. A broadband data stream can be generated by the broadband communication device. The broadband data stream and the LMR identifier can be communicated from the broadband communication device via an access network. The LMR identifier can enable synchronization of the LMR data stream with the broadband data stream.

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 semiconductor device capable of communicating with a host apparatus includes a symbol generation unit, a coding unit, and a transmission unit. The symbol generation unit includes a random number generation circuit and generates a symbol according to a random number generated by the random number generation circuit. The coding unit performs 8b/10b coding for the symbol. The transmission unit transmits the symbol coded by the 8b/10b coding unit to the host apparatus.

Abstract: Systems and methodologies are described that facilitate synchronizing base stations in a wireless communication environment. A base station can receive a synchronization signal sent via a low reuse channel, which can be shared by a group of base stations. Further, the base station can align a clock associated therewith to the received synchronization signal. Moreover, the base station can coarsely align the clock to a first synchronization signal received upon a first subset of resources of the low reuse channel, and finely align the clock to a second synchronization signal received upon a second subset of resources (e.g., of the low reuse channel, of a separate channel, . . . ), where the second subset of resources can be reserved for transmission from at least one base station with at least a predetermined level of synchronous accuracy.

Abstract: A method for self synchronization of a first base station is described. Synchronization information is received from a second base station. The first base station then synchronizes with the second base station using the received synchronization information. Synchronization information may be received from one or more base stations. The second base station may be part of the one or more base stations. A stratum may be determined for each of the one or more base stations. The synchronization information may include a stratum. The second base station may be selected as a synchronizing base station. The second base station may have the lowest stratum.

Abstract: A network of nodes communicating with a central node using a Time Division Multiple Access (TDMA) communications network is disclosed. Each node can synchronize an internal clock with an internal clock of the central node when entering the TDMA communications network using a packet received from the central node. Furthermore, each node can maintain synchronization using subsequent packets communicated in the TDMA communications network and a time slot assigned for the subsequent packet.

Abstract: A system generates one or more media streams from time-stamped packets received over a network. The packets may include audio, video, or a combination of both, sampled at a rate determined by a master media clock at a transmitter of the time-stamped packets or at some other node on the network. Timestamps in the packets may be presentation times based on values of a remote real-time clock at the transmitter that is synchronized with a local real-time clock at a receiver. The system may generate the media streams from the media stream samples and present the sampled data according to the presentation times.

Abstract: A base station apparatus is provided, which includes a generator configured to generate a synchronization signal and a transmitter configured to transmit the generated synchronization signal. The generator is configured to generate a synchronization signal to be mapped on a subcarrier included in one of a plurality of frequency resource candidates that are separated by an interval, which is a common multiple of a determined frequency spacing and a subcarrier spacing between contiguous subcarriers, wherein the subcarrier spacing does not have a value that is a divisor of the determined frequency spacing.

Abstract: Methods and apparatuses for transporting and receiving mobile broadcasting services in order to efficiently provide broadcasting services in a mobile communication system are provided. In the method of receiving mobile broadcasting services, a predetermined transport channel is determined by using service configuration information extracted from a service information channel, at least one transport packet is extracted from the determined transport channel, information about the transport packets is extracted from the transport packets, at least one encapsulation packet including the transport packets is generated by using the information about the transport packets, and application data including the encapsulation packets is generated by using information about the encapsulation packets which is extracted from the encapsulation packets.

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: Disclosed is a random access data transmission system and method using OFDMA. The system includes a scheduling ID into an access grant on a preamble for a random access, and transmits it together with an acknowledgment or a non-acknowledgment of the preamble, a base station uses the scheduling ID to notify the mobile station of a random access data transmittable time and a data transmission channel through a control channel, and the mobile station transmits a preamble in advance. After receiving a transmission assignment instruction corresponding to a scheduling ID through the control channel, the mobile station transmits random access data through an assigned channel.