• Journal of Digital Contents Society
• /
• v.10 no.4
• /
• pp.605-614
• /
• 2009

The software-defined radio (SDR) is a radio communication technology that can reconfigure necessary application software on a common hardware platform to deal with several kind of radio communication environment. It is necessary for a system that can control and analyze functionalities of a system in order to verify the SCA-based reconfigurable middleware platform, SCARLET that implements the SDR technology. In this paper, we propose and implement the architecture of the waveform manager that is connected with SCARLET and performs management and control functionalities. We verify the performance of the waveform manager by testing each functionality of the overall system that uses the SCARLET middleware platform.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.10
• /
• pp.1181-1187
• /
• 2014

In this paper, we implemented polar transmitt converter based on software for next generation digital wireless communication system. The implemented converter converted from rectangular to polar by CORDIC algorithm, and be made up of sweep for DDS output frequency using software control. The implemented converter shows can frequency control up to 1.16GHz within DDS frequency control range by software control. it means that transmitter can be control of varied blocks such as gain, phase, output and etc.. The implemented converter can be applied digital wireless communication system based on SDR.

• The Magazine of the IEIE
• /
• v.33 no.2 s.261
• /
• pp.17-28
• /
• 2006

• Journal of Communications and Networks
• /
• v.10 no.1
• /
• pp.55-62
• /
• 2008

Bandpass sampling (BPS) techniques for the direct down-conversion of RF bandpass signals have become an essential technique for software defined radio (SDR), due to their advantage of minimizing the radio frequency (RF) front-end hardware dependency. This paper proposes an algorithm for finding the minimum BPS frequency for simultaneously down-converting multiple RF signals through full permutation over all the valid sampling ranges found for the multiple RF signals. We also present a scheme for reducing the computational complexity resulting from the large scale of the purmutation calculation involved in searching for the minimum BPS frequency. In addition, we investigate the BPS frequency allowing for the guard-band between adajacent down-converted signals, which help lessen the severe requirements in practical implementations. The performance of the proposed method is compared with those of other pre-reported methods to prove its effectiveness.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.4A
• /
• pp.387-393
• /
• 2008

In this paper, we present an SDR (Software Defined Radio) handset modem platform which supports communication systems such as HSDPA (High Speed Downlink Packet Access), and WiBro (Wireless Broadband Portable Internet). The proposed SDR platform employs DSPs (Digital Signal Processors), FPGAs (Field Programmable Gate Arrays), and microprocessors in such a way that the various communication functions like HSDPA and WiBro can be programmed and downloaded to the hardware platform. The proposed SDR platform can be used for functional verification of the physical layers of the mobile handset system in the mobile communication network. We first demonstrate the receiving structure of the physical layer of the HSDPA and WiBro system. Then, the hardware implementation of the proposed SDR platform is shown with functions and optimized signal flows required at each mode. Finally, the link performance of each mode operating on the proposed SDR platform is presented through the internal loopback tests with the test vectors. The experimental performance has been compared with the computer simulation results.

• Proceedings of the IEEK Conference
• /
• 2004.06a
• /
• pp.257-260
• /
• 2004

This paper describes the software download framework for SDR(Software Defined Radio). SDR is expected to solve the compatibility problem among various mobile communication standards so that people can use the same device for different wireless network. We integrated the SDR software download process into Jini architecture, and modified Jini's several functions. We implemented this proposed framework on a Linux and windows operating systems with Java programming language. With Java platform, we can easily transfer this framework into hand-held devices.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.8 no.1
• /
• pp.117-123
• /
• 2012

This paper implements mobile Worldwide Interoperability for Microwave Access (WiMAX) receiver using Software Defined Radio (SDR) technology. SDR system is difficult to implement on the mobile handset because of restrictions that are computing power and under space constraints. The implemented receiver processes mobile WiMAX software modem on Open Multimedia Application Platform (OMAP) System on Chip (SoC) and Field Programmable Gate Array (FPGA). OMAP SoC is composed of ARM processor and Digital Signal Processor (DSP). ARM processor supports Single Instruction Multiple Data (SIMD) instruction which could operate on a vector of data with a single instruction and DSP is powerful image and video accelerators. For this reason, we suggest the possibility of SDR technology in the mobile handset. In order to verify the performance of the mobile WiMAX receiver, we measure the software modem runtime respectively. The experimental results show that the proposed receiver is able to do real-time signal processing.

• Journal of Space Technology and Applications
• /
• v.2 no.2
• /
• pp.121-136
• /
• 2022

Automatic Identification System used in ship communication is required for marine control way, including monitoring of vessel operation in coastal and exchanging of information for safety navigation between them. But, it uses a very high frequency band of approximately 160 MHz, and at the same time, due to the curvature of Earth, there is a limit to the communication distance. Several demonstrations were made successfully over satellite, but not much work has been done yet through cube-satellite which has low-orbit at 500 km altitude. Here, we demonstrate a reception test of AIS (automatic identification system) receiver for a cube-satellites using software-defined radio (SDR). We collected AIS data from ship at port of Busan, Korea, using R8202T2 SDR and established to transmit them using Adam-Pluto and Matlab Simulink. The process of weakening the signal strength to a satellite was constructed using attenuator. Through above process, we demonstrated whether AIS data was successfully received from the AIS payload.

• Proceedings of the IEEK Conference
• /
• 2002.06a
• /
• pp.395-398
• /
• 2002

본 논문은 Global loaming, backward compatibility, 그리고 multi-standard가 요구되는 미래의 통신시스템에 대한 해답인 Software Defined Radio에 관한 글로서 SDR의 개념과, 그 접근 방법에 대해서 논하고자 한다. 특히 3세대 이동통신인 WCDMA system을 모델로 하여, 그 접근방법에 대해 살펴본다. SDR의 발전은 크기, 무게, 전력소모의 문제와, 전용의 하드웨어 없이 동작할 때의 성능저하를 문제를 해결해야 한다. 여기서 그 해결방안으로 SoC와 Multi-CPU의 방법을 제시하고자 한다.

• Proceedings of the IEEK Conference
• /
• 2001.09a
• /
• pp.825-827
• /
• 2001

SDR(Software Defined Radio)은 여러 세대의 이동 통신 시스템 무선방송 및 다양한 통신 시스템이 존재하는 환경에서 소프트웨어 업그레이드로 무선장치 및 서비스를 제공할 수 있는 효율적인 해결 방안으로 대두되고 있다. SDR 이라는 기술은 하드웨어 수정 없이 모듈화 된 소프트웨어의 변경만으로 단일의 송수신 시스템을 통해 다수의 무선 통신 규격을 통합 수용하는 무선 인터페이스 기술이다[1]. 이러한 기술을 실현하기 위해서는 소프트웨어 다운로드 기술이 매우 중요하게 된다. 왜냐하면 시스템에 프로그램을 다운로딩해서 하드웨어가 Reconfiguration 되어 사용자가 원하는 대로 시스템이 셋팅이 될 수 있어야 하기 때문이다. 소프트웨어 다운로드 방법에는 크게 공중파를 이용하는 방법, 컴팩트한 이동식 디바이스로부터 다운로딩 받는 방법, 전화나 케이블 서비스 등을 통해 근거리/원거리 호스트 서버로부터 소프트웨어를 다운로딩 받는 방법, 네트워크를 통해서 소프트웨어를 다운로드 하는 방법 등이 있다[2]. 이 중에서 본 논문에서는 SDR을 위한 임베디드 시스템을 구현 하였고, 리눅스 포팅을 하였으며 스마트 카드를 이용한 소프트웨어 다운로드 방범을 제시함으로써 SDR 의미 구현을 시도해 보았다.