Deuk-Su Lyu

4G vision and technology development in Korea

With increasing end user demands for wider service due to the rapid growth and variety of IT (information technology) industry, the service with the data rate of 30 Mbps cannot accommodate the future mobile multimedia environment. Therefore, worldwide radio and mobile communication institutes and companies started the R & D of 4G mobile communications system prior to completing the implementation of IMT-2000 system and providing its service. ETRI is one of those organizations endeavoring for the future 4G system with capabilities beyond IMT-2000. With the establishment of R & D project for 4G radio transmission system in January of 2002, ETRI is actively working to develop 4G high-tier system, HMM (high-speed mobile Internet), and Hpi (high-speed portable Internet). In this paper, ETRIs 4G vision and enabling technologies to achieve this vision is described.

Implementation of wideband CDMA modem using processors and programmable logic devices

This paper describes the design and implementation of wideband code division multiple access (CDMA) modem of Base Station Transceiver Subsystem (BTS) for a testbed of 4.096 megachips/second (Mcps) CDMA Personal Communication System (PCS). The physical layer of an applied CAI is introduced, and the structure of BTS is explained. The implemented modem consists of programmable logic devices (PLDs) and digital signal processing processors (DSPs) running at 25 mega-instructions per second (MIPS). The modem structure is described, along with functions in DSPs, and computing time of main functions for DSPs to take on the heaviest burden a traffic channel among five kinds of channels, except for searching of code acquisition.

Architecture of base station transceiver for assessing wide band CDMA-based common air interface

This paper describes the structure of Base Station Transceiver Subsystem (BTS) for a wide band direct sequence code division multiple access (CDMA) Personal Communication Service (PCS) testbed. The testbed set out with the aim to demonstrate a prototype CDMA system offering toll quality speech with 32 kilo-bits per second (Kbps) adaptive differential pulse code modulation (ADPCM). The testbed design needs to consider the main requirements such as modularization of flexible hardware to easily find out a proper common air interface (CAI) in real environment, and verification and validation of the CAI. The CAIs characteristics are explained, and the design philosophy and the structure of the BTS along with allocated functionalities are described. Test status of the BTS on functions is provided.

Development of 3.6 Gbps RF Transceiver for Wireless Nomadic Local Area Networks

We present high data rate wideband transceiver design and experimental evaluation for 3.62 Gbps wireless transmission systems in this paper. The present system provides high definition moving picture and contents in a real-time wireless environment at home, offices or class rooms of universities. Also, the present platform provides a test platform for the Giga level high throughput wireless communication system using the OFDM method and the multiple antennas.