Samsung Electronics Co., Ltd.

Su-Won Park

Jae-min Ahn

Young-Ky Kim

Soon-Young Yoon

Hee-Won Kang

Jae-Yeol Kim

Jae-Yoel Kim

Yong-Jun Kwak

Ho-Kyu Choi

Jin-Soo Park

Hun-Kee Kim

Yong-Suk Moon

Jin-Woo Choi

Jae-Seung Yoon

Jong-Han Kim

Joong-Ho Jeong

Hyun-Kyu Lee

Jae-Heung Yeom

Sang-Hwan Park

Hyun-Jung Mun

Jae-Hoon Chung

Doo-Gyun Kim

Jae-Min C/O Samsung Electronics Co Ltd Ahn

Hee-Won c/o Samsung Electronics Co Ltd Kang

A transmitter simultaneously performs channel coding and rate matching in a CDMA mobile communication system. The transmitter encoders input bits into coded bits at a given mother code rate, and performs puncturing on the coded bits in order to match the number of coded bits to a predetermined code rate. Thereafter, the transmitter simultaneously performs rate matching for repeating or puncturing the coded bits in order to match the number of coded bits to the number of bits transmitted over a radio channel.

Apparatus and method for performing coding and rate matching in a CDMA mobile communication system

A base station device for a CDMA communication system includes a controller for changing a reference value for reverse closed loop power control in a control hold state, and a forward dedicated control channel transmitter for transmitting a power control bit for controlling transmission power of a reverse link according to the changed reference value.

Reverse closed loop power control in control hold state for CDMA communication system

A mobile station device and method which includes a preamble generator for generating a preamble signal intermittently to be transmitted during a preamble interval prior to a transmission interval of a reverse access channel message; and a transmitter for spreading and modulating the preamble signal received from the preamble generator and transmitting it to a base station.

Device and method for transmitting preamble of access channel in mobile communication system

A receiving device for a mobile station receives signals transmitted from a base station having a time-switched transmission diversity (TSTD) function. In the receiving device, a despreader despreads channel signals which have been transmitted in a TSTD mode of operation. A pilot separator separates a pilot signal from the despread channel signals. A channel estimator generates a channel estimation signal by selecting pilot signals transmitted from a same antenna of a transmitter according to a TSTD pattern of the transmitter. A compensator compensates the channel signals with the channel estimation signal.

Device and method for mobile station for receiving signals transmitted from a base station

A handoff implementing device and method in a mobile communication system. The handoff implementing device including a base station transmitter and a mobile station receiver. The base station transmitter divides a given frame period into a transmission period and a non-transmission period, separates frame data in the frame period into first and second data, spreads the first and second data by different orthogonal codes, and transmits the spread signal in the transmission period. The mobile station receiver receives the first and second data spread by the different orthogonal codes in the transmission period, assembles the first and second data into the frame data, and searches for an adjacent base station to which a call is handed off in the non-transmission period.

Device and method for implementing handoff in mobile communication system

An orthogonal code hopping multiple access communication system divides channels according to hopping patterns of the orthogonal codes allotted to the respective channels. The communication system includes a transmitter for modulating input digital signals using an orthogonal code hopping multiple access technique and transmitting the modulated digital signals, and a receiver for receiving the digital signals using the orthogonal code hopping multiple access technique and restoring the digital signals.

Orthogonal code hopping multiple access communication system

A method for performing a handoff when a mobile station receiving a transmission diversity signal travels from a first base station transmitting a signal in a transmission diversity mode of operation to a second base station transmitting a signal in the transmission diversity mode of operation. In the method, the mobile station communicates with the first base station in the transmission diversity mode of operation. Prior to performing handoff, the mobile station communicates with the first base station in a non-transmission diversity mode of operation. During the handoff, the mobile station communicates with the first and second base stations in the non-transmission diversity mode of operation. Upon completing the handoff, the mobile station communicates with the second base station in the non-transmission diversity mode of operation. After a predetermined time, the mobile station communicates with the second base station in the transmission diversity mode of operation. Other methods for performing the handoff are also provided where, for example, the mobile station and the base stations operate in the transmission diversity and the non-transmission diversity modes of operation.

Handoff method in a mobile communication system supporting transmission diversity

A PN sequence identifying device in a receiver in an asynchronous CDMA communication system. The receiver receives first OGCs on a primary sync channel and second OGCs on a secondary sync channel synchronized with the primary sync channel symbol by symbol. In the PN sequence identifying device, a first OGC detector detects the first OGCs and obtains a first symbol energy. A first synchronizer receives the first symbol energy, synchronizes chips, symbols, and slots, and outputs a first sync signal. A second OGC detector, upon reception of the first sync signal, detects the second OGCs each time the first sync signal is received, and obtains second symbol energies in base station identifying group units. A hopping pattern generator compares the first symbol energy with the second symbol energies, determines whether null signs are in the second OGCs, determines the order of the null signs if the null signs are present, and generates a hopping pattern of the second OGCs. A second synchronizer synchronizes frames based on the hopping pattern and outputs a second sync signal. A PN sequence generator receives the first and second signals and the hopping pattern and generates a PN sequence.

PN sequence identifying device in CDMA communication system

In a code division multiple access (CDMA) communications system, a PN sequence generating device is provided to generate a PN sequence by interleaving of cyclically shifting the symbols of an orthogonal or biorthogonal code in accordance with a pre-defined hopping pattern. A receiver receives simultaneous signals from a plurality of transmitters, where each transmitted signal is spread by a PN sequence generated from the same pre-defined hopping pattern. The receiver is able to differentiate the received signals from each transmitter by varying the amount of interleaving or cyclic shift in each transmitted signal. In the PN sequence generating device, an orthogonal symbol generating portion cyclically shifts mutually orthogonal and periodic orthogonal code sequences, and an orthogonal symbol selector selectively outputs the cyclically shifted orthogonal symbols according to a predetermined pattern.

Device and method for generating PN sequence in CDMA communication system

A base station and a mobile station for a CDMA communication system intermittently exchange data on a power control group unit or time slot unit in a control hold state to minimize interference. To this end, during channel transmission, the system intermittently transmits a reverse pilot channel signal in the control hold state; upon activation of a reverse dedicated control channel, transmits a normal pilot channel signal which is first generated after activation of the reverse dedicated control channel; and then transmits the reverse dedicated control channel.

Gated transmission in control hold state in CDMA communication system

A device and method for cancelling code interference in a receiver of a CDMA (Code Division Multiple Access) communication system simultaneously using orthogonal codes and quasi-orthogonal codes are provided. In a receiver according to an embodiment of the present invention, a channel estimator produces a channel estimation value of a pilot channel signal spread by an orthogonal code through despeading. A quasi-orthogonal channel receiver receives a channel signal spread by a quasi-orthogonal code, despreads the channel signal, demodulates the despread channel signal by use of the channel estimation value, and provides an output. An interference estimator estimates an interference value of the pilot channel signal with the channel signal spread by the quasi-orthogonal code by obtaining a correlation value between the orthogonal code corresponding to a pilot channel and the quasi-orthogonal code corresponding to a quasi-orthogonal channel. An interference canceller cancels the estimated interference from the output of the quasi-orthogonal channel receiver.

Device and method for cancelling code interference in a CDMA communication system

Packet data communicating device and method in a CDMA communication system. According to a first embodiment, a transmitting device for a base station includes a data generator for generating frame data to be transmitted, a first mask generator for generating a long code mask for a forward common channel, a second mask generator for generating a long code mask for a forward common channel to be designated as dedicated to a specific mobile station, a selector for selecting one of the long code masks generated in the first and second mask generators, a long code generator for generating a long code with the selected long code mask, a scrambler for mixing the frame data received from the data generator and the long code received from the long code generator, and a transmitter for spreading the scrambled frame data, for transmission.

Device and method for communicating packet data in mobile communication system

A reverse power control method allows a base station to control transmission power of terminals. To this end, the base station sets a threshold value for the reverse power control, determines the number of the terminals requiring an increase in the transmission power and compares the determined number with the threshold value. If the determined number is equal to or greater than the threshold value, the base station commands the terminals to reduce the transmission power. However, if the determined number is smaller than the threshold value, the base station commands the terminals to increase the transmission power.

Reverse power control device and method for reducing interference between terminals

A method for preventing a collision among access requests made from a plurality of mobile stations requesting access to a base station in a radio communication system having a plurality of forward link and reverse link access channels. The base station allocates one of the forward link channels as a broadcast channel and transmits channel information about currently available reverse link access channels to the mobile stations via the broadcast channel. Based on the channel information received via the broadcast channel, one or more of the mobile stations transmits an access request signal to the base station via a selected one of the currently unoccupied reverse link access channels. Upon receipt of an access approval signal from the base station, the access requested mobile station accesses the base station via the selected unoccupied access channel.

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Seoul, South Korea

Su-Won Park