Abstract:
A random access channel operating method in a mobile communication system is provided. The random access channel operating method includes: (a) selecting a transmission mode according to a load of a random access channel and performing transmission to a mobile terminal; (b) receiving a message having a format corresponding to the selected transmission mode from the mobile terminal; (c) determining whether or not a preamble or data is included in the message received in (b) receiving of the message; and (d) if the data is determined to be included in the (c) determining, transmitting a response message for data reception to the mobile terminal. Accordingly, use efficiency of a random access channel can be increased by measuring a system load of the random access channel in a base station and changing a transmission format of a burst transmitted through the random access channel according to the measured load level.
Abstract:
To transmit resource allocation information on a plurality of radio resources to a terminal, a resource allocation device expresses a radio resource that is differently allocated from before the resource allocation information is transmitted among the plurality of radio resources in a radio resource pattern sequence, generates resource allocation information on the plurality of radio resources based on the radio resource pattern sequence, and transmits the radio resource pattern sequence and the resource allocation information, or a compressed pattern sequence corresponding to the radio resource pattern sequence and the resource allocation information, to the terminal through a frame.
Abstract:
In order to allocate a plurality of terminals to a group in a base station of a communication system, channel state information of each of the terminals is received, a group to which the terminal belongs is determined according to the channel state information with respect to the terminal, and a map including information on group burst allocation and information on sub-burst allocation with respect to a group identifier corresponding to the group is transmitted to the terminal.
Abstract:
The present invention relates to a multi-input multi-output (MIMO) system for enhancin transmission performance. The MlMO system uses space-time encoding and transmi antenna selection methods, and includes a transmitter (100) and a receiver (200). Th transmitter (100) includes N transmit antennas (130-1 , 130-4) that are more than M tansrni antennas (130-1 , 130-3) used for tansmitting a signal to space channel, selects the M transmi antennas (130-1, 130-3) among the N tansmit antennas (130-3 130-4), and tansmits symbol by space-time encoding the symbol. The receiver (200) includes M receive antenna (120-1 , 210-2) for receiving a signal from the space channel, detects an information symb by using the signal received through the receive antenna (210-1 , 210-2), generates transmi antenna selection information for selecting M transmit antennas (130-1 , 130-3) among tansmit antennas (i30-1,...7130-4) with reference to a channel estimate, and returns th information to the tansmitter.
Abstract:
Disclosed are an uplink synchronization request method in a mobile communication system, a CDMA allocation information element structure thereof, and a portable subscriber station (PSS) using the same. For this purpose the uplink synchronization request method includes: when uplink traffic is generated, determining whether an uplink synchronization error occurs; when the uplink synchronization error occurs, calculating a timing adjustment value; and transmitting a bandwidth request code including the calculated timing adjustment value to a base station and performing a bandwidth request. According to the present application, the PSS compares a reference adjustment value and an arrival time of a downlink preamble to calculate uplink synchronization timing and synchronize an uplink of the PSS that requests bandwidth allocation through a bandwidth request ranging process to thereby maximize resource use efficiency in the uplink synchronization.
Abstract:
In order to perform uplink scheduling for a terminal, a base station receives information on uplink interference due to the terminal from neighbor base stations, transmits the information on the uplink interference to the terminal, receives information on transmission power of a feedback channel from the terminal through the feedback channel, compares the transmission power of the feedback channel and reception power of the feedback channel so as to estimate transmission loss, and performs uplink scheduling for the terminal by reflecting the transmission loss.
Abstract:
Provided is a method and apparatus for common packet channel access to transmit data packet from a mobile terminal to a satellite access network in a mobile satellite communication system. The method and apparatus of this invention reduces transmission delay time, enhances the probability of successful access, and controls the currently used common packet channel by using a common control channel broadcast by the satellite access network. The method includes the steps of: receiving an access preamble including an access signature code and a collision-detection preamble including a collision-detection signature code, which are transmitted together from a plurality of mobile terminals, and transmitting an acknowledgement to the access preamble and collision-detection preamble to mobile terminals through a preamble acknowledgement channel.
Abstract:
The present invention relates to Random Access Channel (RACH) access apparatus for mobile satellite communication system and method therefor. The method for accessing random access channel (RACH) on satellite system, random access channel (RACH) carrying message from a plurality of mobile stations to the satellite system, the method includes the steps of: receiving preamble and the message, the message successively transmitted with the preamble from the plurality of mobile stations; and transmitting acquisition response signal corresponding to the preamble or the message to the plurality of mobile stations. Accordingly, success of packet reception of satellite system is improved and transmission delay is reduced.
Abstract:
Disclosed is an apparatus for transmitting feedback information to a base station. The feedback information transmitting apparatus receives channel allocation information, generates a plurality of payloads regarding feedback information, and multiplexes the plurality of payloads in terms of a plurality of classes so as to generate a plurality of multiplexed payloads. Subsequently, the plurality of multiplexed payloads are code multiplexed so as to generate a code division multiplexing symbol, and a channel code is applied to the code division multiplexing symbol. Then, the code division multiplexing signal applied with the channel code is transmitted to a base station through a wireless resource. Accordingly, a feedback channel that is adaptive to a channel condition is configured, such that a wireless resource for a feedback channel can be efficiently used.
Abstract:
The present invention relates to a method of constructing a resource allocation map in a mobile communication system. In a method of constructing a map in a hierarchial pattern method in a case where a localized resource block (localized RB) and a distributed resource block (distributed RB) need to be simultaneously allocated in regards to a radio resource allocated in a previous frame or reserved with a fixed allocation, a radio resource that is reserved or not used and a radio resource that is newly allocated in a map of a current frame are classified and represented. Then, in regards to a radio resource that is allocated in a current frame, a localized RB and a distributed RB are classified and represented. As for the localized RB, allocation information is represented in an index pattern method, and as for the distributed RB, resource allocation information is represented in a toggle pattern method.