Electronics and Telecommunications Research Institute

Duck-Bin Im

In-Myoung Jeong

Ki-Chul Han

Dong-Wook Lee

Sang-Cheon Lee

Hyun Woo Lee

Ki-Hong Kim

Whan-Woo Kim

Min-Sik Seo

Seok-Ho Won

A base station system of a multicarrier CDMA and a data transmission method and a mobile communication system using the same are disclosed. The system includes a base station control apparatus connecting with an exchange, a pilot signal modulation apparatus for generating a spread spectrum modulated pilot signals as many as the number of carriers in accordance with a control of the base station control apparatus, a paging signal modulation apparatus for generating a spread spectrum modulated paging signals as many as the number of carriers in accordance with a control of the base station control apparatus, a plurality of traffic signal modulation apparatuses for generating a spread spectrum modulated traffic signals as many as the number of carriers in accordance with a control of the base station control apparatus, a plurality of combiners provided as many as the number of the carriers for combining input signals from the modulation apparatuses, and a radio frequency transmission apparatus for modulating the outputs from the combiners into multiple radio frequencies and transmitting the same, for thereby controlling a lot number of mobile stations by distinguishing the mobile station signals using an orthogonal codes at a link from a base station to a terminal in the multicarrier CDMA cellular system and removing a interference between the mobile stations in the same cell.

Base station system and data transmission method of multicarrier CDMA/FDM hybrid system and mobile communication system using same

A base station system of a multicarrier CDMA and a data transmission method and a mobile communication system using the same are disclosed. The system includes a base station controller connected with an exchanger for generating random phase values as much as the number of carriers when a call set-up is requested and for outputting a paging information containing the phase values, a pilot signal modulation unit for generating a spread spectrum modulated I-phase pilot signal and Q-phase pilot signal as many as the number of the carriers in accordance with a control of the base station controller, a paging signal modulation unit for generating a spread spectrum modulated I-phase paging signal and Q-phase paging signal having predetermined phase differences compared to the pilot signal as many as the number of the carriers, a plurality of traffic signal modulation units for generating, as many as the number of the carriers, a spread spectrum modulated I-phase traffic signal and Q-phase traffic signal having phase differences between the carriers as much ad the phase transition values inputted from the base station controller compared to the pilot signal, and a plurality of combiners for combining the I-phase signal and Q-phase signal, respectively, inputted from each modulation apparatus corresponding to a corresponding one of the carriers.

Multicarrier CDMA base station system and multi-code wave forming method therof

An adaptive power control method for a CDMA mobile radio telephone system is disclosed which operates similarly to a fixed increment and decrement power control method in the portion where the slope of the channel signal due to a fading effect is steep when the transmission power of a mobile station is adjusted. In the portion where the slope of the channel signal is gentle, like the peak portion of the channel signal, the granular noise can be improved by using the Jayant's equations. In accordance with the present invention, the fading effect in the mobile radio channel can be efficiently compensated without giving much load to a forward link since a mobile station determines the variation of the backward channel signal by using the statistical characteristics of a power control command (1 bit) transmitted from a base station. Further, an amount of interferences among a plurality of users can be reduced because the variation (variance) of a receiving power at the base station caused by the fading effect in each mobile station is made small. Thus, the overall performance of the system can be significantly improved in accordance with the present invention.

Adaptive power control method for a CDMA mobile radio telephone system

An improved CDMA mobile automatic call simulating method and a simulator therefor which are capable of computing an accurate statistic data by repeating an actual CDMA call attempt and call incoming and by judging the result of the call attempt, which includes a management unit for communicating with the mobile stations and controlling the same in accordance with a previously set protocol, and a connection unit for communicating with the management unit and the mobile stations in accordance with an SDLC in an RS-422 signal method.

CDMA mobile automatic call simulating method and simulator therefor

An automatic call simulator for simulating call processing capacity and performance between a base station and a mobile station of a CDMA mobile communication system is disclosed. A mobile station has a communication port for serial communication with an external unit. An operating unit controls all the mobile station by operating software, generates the state of each mobile station during simulation and a simulation result, and records simulation result data. An interface unit for interfacing the mobile station with the operation unit is included within a metal box so as not to be influenced by an external electromagnetic wave and has external terminals connected to the mobile station and to the operation unit. The interface unit and the mobile station are connected through the communication port.

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Taejon, South Korea

Duck-Bin Im