摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.