Abstract: Disclosed is an apparatus for generating an error detection information bit sequence for determining a length of data sequence transmitted in a communication system. The apparatus comprises a plurality of cascaded registers, the number of which is identical to the number of bits in the error detection information bit sequence, and a plurality of adders arranged on paths determined by a predetermined generator polynomial, each of the adders adding a bit sequence received through an input path to a feedback bit sequence. During reception of the control information sequence, an operator generates the feedback bit sequence by sequentially adding bits of the control information sequence to output bits of a final register and provides the generated feedback bit sequence to the adders. After completion of receiving the control information sequence, the operator sequentially adds a preset input bit to output bits of the final register and outputs the addition result as the error detection information bit sequence.

Abstract: An apparatus and method for transmitting/receiving a PDCCH (Packet Data Control Channel) for efficient packet data transmission in a communication system supporting packet data service. To allow both TDM-transmission and TDM/CDM-transmission of packet data, PDCCHs having different control information are transmitted. A 1PDCCH and a 2PDCCH are selectively transmitted according to the channel environments of users to thereby minimize the transmission power of the 1PDCCH and the 2PDCCH. A PDCCH receiver receives the 1PDCCH and the 2PDCCH using Walsh functions assigned to them, demodulates them, and checks errors in them, thereby obtaining control information about packet data to be received.

Abstract: An apparatus and method for transmitting/receiving a PDCCH (Packet Data Control Channel) for efficient packet data transmission in a communication system supporting packet data service. To allow both TDM-transmission and TDM/CDM-transmission of packet data, the PDCCH has a different format depending on the transmission scheme of the packet data. A receiver operates in BSD (Blind Slot Detection) to detect the transmission scheme of received packet data and the format of the PDCCH.

Abstract: Disclosed is an apparatus for performing power control on a reverse channel quality indicator channel (CQICH) received from a mobile station by a base station in a mobile communication system including the base station for transmitting a power control bit for power control on reverse channels and the mobile station for controlling transmission power of the reverse channels according to the power control bit. An erasure detector determines whether to perform an erasure process by measuring reception power of the reverse channel quality indicator channel. An erasure rate calculator accumulates the erasure-determined result for N slots and calculates an erasure rate for the N slots. A control bit generator determines a ratio control bit to be transmitted to the mobile station according to the erasure rate, to issue a command to increase or decrease a CQICH traffic-to-pilot ratio.

Abstract: A method for controlling power of common power control channels from a plurality of base stations in order to control transmission power of a mobile station in a mobile communication system. The power control method comprises receiving, by the mobile station, pilot signals from the base stations and selecting a base station that transmitted a pilot signal having a highest power level; transmitting information indicating a channel condition between the selected base station and the mobile station, from the mobile station to the selected base station; and controlling power of a common power control channel transmitted from the selected base station to the mobile based on the channel condition information received from the selected base station.

Abstract: An apparatus and method for transmitting and receiving forward channel quality information between a base station and a mobile station in a CDMA mobile communication system supporting multimedia service including voice and data services. The mobile station transmits an absolute value symbol in at least one time slot selected from a plurality of time slots, and a relative value symbol in one of the remaining time slots. The absolute value symbol represents the signal strength of the forward channel in the at least one time slot corresponding to the selected time slot, and the relative value symbol represents a change in the signal strength of the forward channel between the at least one time slot corresponding to the one remaining time slot and the signal strength of the forward channel in a previous time slot.

Abstract: A power control method during a soft handoff in a mobile communication system. A mobile station communicating with a plurality of base stations at a soft handoff measures the signal strengths of forward common pilot channels received from the base stations and transmit them to the base stations sequentially. Then the base stations control the transmission power of forward common power control channels according to the received signal strength measurements.

Abstract: Disclosed is an apparatus and method for transmitting R-RICH (Reverse Rate Indicator Channel) in a CDMA (Code Division Multiple Access) mobile communication system. There is provided an encoding/decoding apparatus and method for generating optimal codewords for optimal (24,1) encoding to optimal (24,7) encoding, and supporting all of an optimal (24,1) encoder to an optimal (24,7) encoder.

Abstract: A reverse data transmission apparatus and method in a mobile communication system. A mobile station receives information about an MADR (Maximum Allowable Data Rate) from a base station in a first predetermined frame period, determines a data rate equal to or lower than the MADR, and requests the determined data rate to the base station. If an MADR received from the base station in a second frame period following the first frame period is higher than the requested data rate, the mobile station starts data transmission. Then, the mobile station measures a traffic to pilot ratio (T/P) from the base station and controls the data rate according to the T/P during data transmission.

Abstract: A base station transmission apparatus for transmitting MAC (Medium Access Control) ID (Identification) information indicating a terminal to receive transmission packet data and length information of the transmission packet data in a mobile communication system for high-speed packet transmission, having an encoder for encoding a bit stream indicating the MAC ID information and generating coded symbols; a Walsh cover section for Walsh-covering the coded symbols from the encoder with a Walsh code based on the length information; and a Walsh spreader for spreading the Walsh-covered symbols from the Walsh cover section with a predetermined Walsh code.

Abstract: An encoding method in a mobile communication system, for receiving 4 input information bits, encoding the 4 input information bits with different Walsh codes of length 16, and outputting a coded symbol stream having 24 coded symbols using a coded symbol stream having 16 coded symbols obtained by XORing the encoded input information bits by an XOR operator. The encoding method comprises repeating the coded symbol stream having 16 coded symbols once, and thus outputting a coded symbol stream having 32 coded symbols; and puncturing 0th, 1st, 2nd, 3rd, 4th, 5th, 6th and 16th symbols from the 32 coded symbols, and thus outputting the coded symbol stream having 24 coded symbols.

Abstract: There are provided a method and device for transmitting/receiving reverse data rate information in a mobile communication system supporting multimedia service applications including voice and data services. According to the present invention, upon receipt of information about the maximum data rate of an SCH, a mobile station determines the minimum number of bits to be assigned to the reverse data rate information according to the number of data rates less than or equal to the maximum data rate and then transmits the reverse data rate information with the minimum number of bits to a base station.

Abstract: Disclosed is an apparatus and method for generating a QCTC (Quasi-Complementary Turbo Code) considering a characteristic of a turbo code in a packet communication system or a communication system using an ARQ (Automatic Repeat reQuest) scheme. There is provided a method for transmitting a sub-code determined by a sub-code rate identical to or different from a code rate of a turbo encoder according to a channel environment from a QCTC generated by the turbo encoder receiving an information stream and operating at the code rate.

Abstract: Disclosed is provided a method for switching an operation mode from a non-USTS to a USTS mode in a Node B capable of communicating with a UE in both the non-USTS mode and the USTS mode. The Node B calculates a difference value between a start point of a downlink dedicated channel frame in a downlink dedicated channel transmitted to the UE in the non-USTS mode and a start point of an uplink dedicated channel frame in an uplink dedicated channel received from the UE. The Node B determines a first control value for controlling the start point of the uplink dedicated channel frame in the uplink dedicated channel by comparing the difference value with a given reference value, and also determines a second control value such that the second control value for the start point of the downlink dedicated channel frame in the downlink dedicated channel becomes a multiple of a given number of chips.

Abstract: An apparatus encodes 7 input bits into 24 symbols in a mobile communication system. In the apparatus, an encoder encodes 7 input bits into 32 symbols using an extended Reed-Muller code created from a Gold sequence, and a puncturer punctures 8 symbols from the 32 symbols provided from the encoder according to a predefined puncturing pattern, and outputs 24 non-punctured symbols.

Abstract: An apparatus randomly assigns downlink sub-frame time slots for transmitting user data in an NB-TDD CDMA (Code Division Multiple Access) communication system. In the apparatus, a multiplexer creates a user data part by multiplexing user data for a UEs (User Equipments), a TFCI (Transport Format Combination Indicator) symbol for the user data, and a TPC (Transmission Power Control command) symbol for controlling transmission power of a downlink channel, and a controller randomly assigns time slots for transmitting the user data part in the sub-frames, based on a time slot number initilly assigned for the user data part, a sub-frame number at a transmission point of the user data part, and the number of assigned uplink time slots in the corresponding sub-frame.

Abstract: An apparatus and method for efficiently distributing energy to a packet data channel. A turbo encoder generates a sequence of systematic symbols and a sequence of parity symbols by encoding an information bit stream. An interleaver interleaves the systematic symbol sequence and the parity symbol sequence, separately and serially concatenates the interleaved systematic symbol sequence and the interleaved parity symbol sequence. An energy distributor rearranges the concatenated symbols so that the systematic symbols are disposed in a high energy-having portion of a predetermined transmission period when transmission energy varies for the transmission period. A modulator modulates the rearranged symbols.

Abstract: A base station PDCCH (Packet Data Control Channel) apparatus for scrambling transmission packet data to prevent other terminals from recognizing the transmission packet data in a base station including a packet data channel device for transmitting packet data to a terminal and a packet data control channel device for transmitting control information needed for demodulation of the packet data to the terminal. In the apparatus, an encoder encodes the control information and generates a coded control information stream comprised of a stream of a plurality of bits. A scrambler generates a scrambling sequence using unique information known to only the terminal and the base station, and scrambles the coded control information stream with the scrambling sequence.

Abstract: There is provided a transmission diversity system. In the case where an MS supporting a different antenna transmission diversity scheme enters the service area of a 4-antenna transmission diversity UTRAN, the UTRAN can transmit pilot signals and common data signals to the MS without the need of modifications to the MS. Therefore, power is distributed among antennas of the UTRAN and system capacity is increased.

Abstract: Disclosed is a mobile station for determining a data rate for a packet data service in a mobile communication system including a base station, and the mobile station being provided with a voice service and a packet data service from the base station. In the mobile station, a receiver receives orthogonal code allocation information indicating the number of orthogonal codes allocated for the packet data service, a measurer measures a CIR using a received pilot channel, and a controller determines a data rate corresponding to the measured CIR, controls the determined data rate based on the number of the allocated orthogonal codes, and determines a controlled data rate.