摘要:
A frequency overlay communication system that includes a first communication system for performing communication using a first frequency band being a preset bandwidth; and a second communication system for performing communication using a second frequency band being a second preset bandwidth, wherein the second frequency band includes the first frequency band.
摘要:
Provided are an apparatus and a method for providing a concurrent data service to an Mobile Station (MS) through a plurality of heterogeneous networks. In a method for providing a data service to an MS through different wireless networks, the MS measures channel qualities of at least one accessible wireless network and reports the measured channel qualities to an Internet Protocol (IP) packet controller. The IP packet controller selects wireless networks for data transmission on the basis of the reported channel qualities, distributes data destined for the MS, and transmits the distributed data to the selected wireless networks. The selected wireless networks receive the data from the IP packet controller and transmits the received data to the MS. The MS combines and interprets the data received from the selected wireless networks. Accordingly, it is possible to provide a seamless data service to the MS in service environments with a mixture of different wireless communication systems.
摘要:
A transmitter for a mobile communication system based on an OFDM scheme and a method for controlling the same. The transmitter can implement a characteristic of a multiple access scheme based on an OFDM scheme, a characteristic of a CDMA scheme, and a characteristic of a frequency hopping scheme which has very strong resistance to the frequency selective fading. An apparatus for transmitting information bit sequences from a BS (Base Station) transmitter to different users, includes a plurality of channelizers for dividing a single frame of information bit sequences to be transmitted to individual users into a plurality of times according to a given time interval, simultaneously transmitting the information bit sequences to the individual users within the plurality of division times, dividing the information bit sequences, spreading the divided information bit sequences using different Walsh codes, converting the spread information bit sequences into a single sequence associated with the individual users, and outputting the single sequence; and a frequency hopper for dividing the single sequence, distributing the spread information bit sequences over a plurality of bandwidths capable of mapping-processing the spread information bit sequences with sub-carrier frequencies, and preventing each of the bandwidths from overlapping with time-frequency cells given by the given time interval.
摘要:
Provided are an apparatus and a method for providing a concurrent data service to an Mobile Station (MS) through a plurality of heterogeneous networks. In a method for providing a data service to an MS through different wireless networks, the MS measures channel qualities of at least one accessible wireless network (913) and reports the measured channel qualities to an Internet Protocol (IP) packet controller (914). The IP packet controller selects wireless networks for data transmission on the basis of the reported channel qualities (918), distributes data destined for the MS (919), and transmits the distributed data to the selected wireless networks (920). The selected wireless networks receive the data from the IP packet controller and transmit the received data to the MS (922). The MS combines and interprets the data received from the selected wireless networks (923,924). Accordingly, it is possible to provide a seamless data service to the MS in service environments with a mixture of different wireless communication systems.
摘要:
Provided is an apparatus and method for communicating a frame in a multi-hop relay cellular communication system. When communicating at a Relay Station (RS), a Downlink (DL) signal is received from a Base Station (BS) and the received DL signal is reconfigured during a first section of a frame. The reconfigured DL signal is transmitted to a Mobile Station (MS) during a second section of the frame. During a third section of the frame, a UL signal is received from the MS and is reconfigured. The reconfigured UL signal is transmitted to the BS during a fourth section of the frame. The RS recovers data from the BS to retransmit only specific data corresponding to the BS.
摘要:
An apparatus and method for transmitting a reference signal in an Orthogonal Frequency Division Multiple Access (OFDMA) communication system in which a total frequency band is divided into a plurality of subcarrier bands. A time division multiplexer performs time division multiplexing such that the reference signal is transmitted for a first duration in a predetermined number of subcarrier bands from among the plurality of the subcarrier bands, and a signal other than the reference signal is transmitted for a second duration other than the first duration. A transmitter transmits the time-division multiplexed subcarrier band signals.
摘要:
Disclosed are a method and a system for transmitting/receiving signals in a mobile communication system using a multiple input multiple output adaptive antenna array scheme. A first receiver calculates a reception weight value by using a de-spread signal of a reception signal for creating a reception beam of the first receiver and calculates a transmission weight value by using the calculated reception weight value for creating a transmission beam of the second transmitter, thereby creating feedback information including the transmission weight value. A first transmitter transmits the feedback information to a second receiver. The second receiver receives the feedback information and the second transmitter detects the transmission weight value from the feedback information received in the second receiver, and creates the transmission beam corresponding to the detected transmission weight value in order to transmit a signal by applying the transmission beam to the signal.
摘要:
A mobile communication system receives a despread signal of a reception signal, and performs a control operation such that a weight for generating a reception beam is calculated using a first technique if a difference between an error value at a current time and an error value at a previous time is greater than an absolute value of a first threshold or the error value at the current time is greater than or equal to a second threshold, and performs a control operation such that the weight is calculated using a second technique if the different between the error value at the current time and the error value at the previous time is less than or equal to the absolute value of the first threshold and the error value at the current time is less than the second threshold.