Patent application number | Description | Published |
20080232518 | Apparatus and Method for Automatic Gain Control of Mobile Station in Ofdm System - The present invention relates to an automatic gain control apparatus and method of a mobile station in an OFDM system. The present invention includes: identifying a preamble section and a data symbol section in a received frame signal; when a current symbol is the preamble section, measuring a power value of a preamble signal, comparing the measured power value of the preamble signal and a threshold value, and amplifying the received frame signal based on a predetermined gain value (gain=threshold−power value) according to a difference between the measured power value and the threshold value; when a data symbol section includes a pilot carrier, measuring an average power value of the pilot carrier in the data symbol when the data symbol section includes the pilot carrier, comparing the measured average power value of the pilot carrier and the threshold value, and amplifying the received frame signal based on a predetermined gain value (gain=threshold−pilot average power value) according to a difference; and when the data symbol section includes no pilot carrier, maintaining an existing gain, or performing an automatic gain control operation according to a gain estimated by using the pilot carrier during the data symbol section including the pilot carrier. Accordingly, the mobile station of the OFDM system that is robust to channel variation and various fading environments may be provided to efficiently perform the automatic gain control. | 09-25-2008 |
20090022083 | METHOD OF SYNCHRONIZING FRAME IN MMR NETWORK - Provided is a method of synchronizing a frame using a cycle prefix (CP) in a mobile multi-hop relay (MMR) network. The frame is synchronized using the CP of the frame after obtaining a frame synchronization using a preamble of the frame, which does not need an additional preamble, so that a preamble necessary for the frame synchronization is transmitted to a subordinate station during a preamble receiving section. | 01-22-2009 |
20090285112 | METHOD FOR MANAGING A RELAY PATH IN WIRELESS COMMUNICATION ENVIRONMENT - A method of managing a relay path in a mobile multi-hop relay (MMR) environment is provided. A relay station (RS) discovers a link quality of neighboring RSs, which is necessary for managing a path, and reports the link quality to a base station (BS). The BS selects an optimal path having a tree-structure based on the reported link quality and informs the RS. Thus, wireless resources can be efficiently used. | 11-19-2009 |
20090318166 | METHOD AND APPARATUS FOR DETERMINING TIMING FOR INITIAL RANGING OF USER EQUIPMENT USING RANGING OF ADJACENT PIECES OF USER EQUIPMENT IN MULTI-HOP MOBILE RELAY SYSTEM - Provided is a method and apparatus for determining timing for initial ranging of user equipment by using ranging of adjacent pieces of user equipment in a multi-hop mobile relay (MMR) system, and more particularly, a method and apparatus for determining timing for initial ranging of user equipment in which a power value and a timing value for periodic ranging of adjacent pieces of user equipment are measured so as to minimize an uplink timing error of abase station. In the MMR system, user equipment transmits an initial ranging code to the base station with irregular timing while not knowing an exact start point of an uplink of the base station. In particular, if the user equipment attempts the initial ranging at the same time as when adjacent pieces of user equipment attempt the periodic ranging and the handover ranging, an error occurs between transmission timing of the initial ranging and uplink timing, thereby acting as an inter-symbol interference (ISI) and inter-channel interference (ICI) of different ranging. As a result, the initial ranging acts as an interference signal in a ranging process of adjacent pieces of user equipment. However, the apparatus and method can minimize a timing error of the initial ranging code of user equipment by avoiding the initial ranging acting as the interference signal. | 12-24-2009 |
20100008284 | RELAYING METHOD OF RELAY STATION(RS) USING A DIRECT RELAYING ZONE IN MULTIHOP RELAY SYSTEM - Provided are a method of relaying a data burst in a relay station (RS) of a multi-hop relay (MMR) system using a direct relay zone, and a system using the method. The RS requests a base station to assign the direct relay zone in a frame in which a demodulation and forwarding scheme that demodulates, and then modulates and transmits a data burst is applied, receives an acknowledgement to the request from the base station, and relays a data burst using the frame in which the direct relay zone is assigned. Accordingly, since a data burst can be relayed within one frame, relay latency can be reduced. | 01-14-2010 |
20100069082 | METHOD FOR CONFIGURATING A FEEDBACK REGION IN WIRELESS COMMUNICATION SYSTEM - Provided is a method of configuring a feedback zone in an uplink zone of a frame. This method is for transmitting feedback data in a wireless communication system. The method sets the feedback zone between a relay station (RS) and a mobile station (MS) in addition to a feedback zone between the MS and a base station (BS), thereby preventing a transmission delay of the feedback data incurred by the RS. | 03-18-2010 |
20100069110 | METHOD OF CONTROLLING POWER OF ACCESS UPLINK USING RELAY STATION AND SYSTEM THEREOF - Provided are a method of controlling power of an access uplink using a relay station (RS) and a system thereof. When a base station (BS) decides that the subject of power control of the access uplink is itself, the BS generates a message for power control of the access uplink based on channel quality measurement information reported from the RS and transmits the power control message to a subscriber station (SS), and when the BS decides that the subject of power control of the access uplink is the RS, the RS generates a message for power control of the access uplink based on channel quality measurement information and transmits the power control message to the SS. Thus, fast power control of the access uplink can be performed. | 03-18-2010 |
20110053496 | METHOD OF DETERMINING TRANSMISSION TIMING IN RELAY STATION - A method of determining transmission timing in a relay station is provided. The relay station in a mobile communication system formed of the relay station and a base station generates a processing capability reporting message including information about the processing capabilities in a down link and an up link of the relay station and transmits the processing capability reporting message to the base station. | 03-03-2011 |