• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.447-450
• /
• 2006

최근 국내외에서 재래식 폭탄의 정확도와 사거리를 향상시킨 정밀 유도 무기에 관한 연구가 활발하게 진행 중에 있다. 국내에서는 국방과학연구소의 주도로 재래식 폭탄에 GAK(GPS Adapter Kit)를 장착하는 연구가 진행 중이다. GAK는 GPS/INS 복합 항법 모듈을 내장한 사거리 연장 유도 키트의 일종으로 폭탄이 투하되면 접혀 있던 날개가 전개되고 이후 날개의 플래퍼론을 구동하여 유도 조종을 수행한다. 복합 항법 모듈은 상용의 MEMS IMU, 내장형 GPS 수신기 및 항법 컴퓨터와 실시간 운영 체제에서 구동되는 항법 소프트웨어로 구성된다. 본 논문에서는 복합 항법 모듈의 비행 시험 결과를 제시하였다. 시험 결과 항법 모듈이 실시간으로 정상적인 동작을 수행하였으며 GPS 유도 폭탄의 유도 조종에 적합한 항법 정보를 제공하였음을 확인하였다.

• Journal of Satellite, Information and Communications
• /
• v.2 no.1
• /
• pp.48-55
• /
• 2007

The system requirement definition, system configuration, major parameters for GNSS ground station development are presented in this paper. GNSS ground station system consists of the GNSS sensor station, up link station and monitoring & control system. The GNSS sensor station consists of navigation receiver subsystem which process the GPS and Galileo navigation signal, automic clock subsystem, meteorological data receiving subsystem and navigation data processing subsystem. To communicate the error correction of navigation fate, GNSS sensor station interface with GNSS Control Center.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.9
• /
• pp.157-164
• /
• 2014

The accuracy of instantaneous passive emitter localization varies with sensing platforms and measurable parameters. Appropriate combination of instantaneous measurable parameters have more accurate localization performance than a single parameter based localization in general. Emitter localization is preferred to use a small number of receivers as possible for the efficiency of strategic management in the field of modern electronic warfare support. For this reason, we compare CRLB (Cramer-Rao lower bound) of two moving platform with various measurable parameters to search a appropriate choice of parameters for the better localization performance through the x-y axis CEP (circular error probable) derived form CLRB. In addition, we present the relation of the localization performance and accuracy of measurable parameters.

• Proceedings of the IEEK Conference
• /
• 2002.06a
• /
• pp.149-152
• /
• 2002

In this paper, an adaptive interference canceller (AIC) Is applied to the space-time coded DS-CDMA system in fading channels with arrival time difference from multiple transmit antennas In a CDMA system, arrival time difference causes not only inter-antenna and Inter-symbol interference but also multiple-access Interference even in a downlink. To mitigate the effect of the Interferences an AIC and ML decoding joint scheme Is proposed fur a space-time coded DS-CDMA system in which an adaptation process of tile AIC is merged in the Viterbi decoding algorithm. The performance of the proposed receiver is evaluated for the system with two transmit antennas. It is shown that the proposed receiver achieves significant performance improvement over the ML decoding receiver without the AIC

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.2 no.1
• /
• pp.109-116
• /
• 1998

In this paper, a back propagation neural network teaming algorithm based on the complex multilyer perceptron is represented for suppressing narrowband interference of the received signals in DS-SS mobile communication system. We proposed neural network adaptive correlator(NNAC) which has fast convergence rate and good performance with combining back propagation neural network and the receiver of DS-SS. We analyzed and proved that NNAC has lower bit error probability than that of traditional RAKE receiver through results of computer simulation in the presence of the tone and narrow-band interference and the co-channel interference.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.44 no.12
• /
• pp.44-53
• /
• 2007

In this paper, we focus on the developments of complex location awareness algorithms for real-time location based service and precise/stable localization in the outdoor. In the case of using galileo satellite system along with GPS, several error factor such as the ionosphere can be reduced for an increment of used frequency and visible satellites. Therefore, localization estimation error is no longer having problems with location awareness. But, chips synchronization error induces the error of acquisition and tracking, and the performance of receiver can be decreased. In order to solve this problem, this paper proposes a correlator for performance improvement of receiver in the precise localization.

• Journal of Cadastre & Land InformatiX
• /
• v.52 no.2
• /
• pp.53-65
• /
• 2022

According to the advancement of the GNSS satellite positioning system, the module of hardware and operation software reflecting accuracy and economical efficiency is implemented in the user sector including the multi-channel GNSS receiver, the multi-frequency external antenna and the mobile app (App) base public positioning analysis software etc., and the multichannel GNSS RTK positioning of the active configuration method (DIY, Do it yourself) is possible according to the purpose of user. Especially, as the infrastructure of multi-GNSS satellite is expanded and the potential of expansion of utilization according to various modules is highlighted, interest in the utilization of multi-channel low-cost GNSS receiver module is gradually increasing. The purpose of this study is to review the multi-channel low-cost GNSS receivers that are appearing in the mass market in various forms and to analyze the utilization plan of the "address information facility investigation project" of the Ministry of Public Administration and Security by constructing the multi-channel low-cost GNSS positioning module based RTK survey system (hereinafter referred to as "multi-channel GNSS RTK module positioning system"). For this purpose, we constructed a low-cost "multi-channel GNSS RTK module positioning system" by combining related modules such as U-blox's F9P chipset, antenna, Ntrip transmission of GNSS observation data and RTK positioning analysis app through smartphone. Kinematic positioning was performed for circular trajectories, and static positioning was performed for address information facilities. The results of comparative analysis with the Static positioning performance of the geodetic receivers were obtained with 5 fixed points in the experimental site, and the good static surveying performance was obtained with the standard deviation of average ±1.2cm. In addition, the results of the test point for the outline of the circular structure in the orthogonal image composed of the drone image analysis and the Kinematic positioning trajectory of the low cost RTK GNSS receiver showed that the trajectory was very close to the standard deviation of average ±2.5cm. Especially, as a result of applying it to address information facilities, it was possible to verify the utility of spatial information construction at low cost compared to expensive commercial geodetic receivers, so it is expected that various utilization of "multi-channel GNSS RTK module positioning system"

• Journal of Satellite, Information and Communications
• /
• v.2 no.2
• /
• pp.48-52
• /
• 2007

Recently, the research of GPS receiver which uses the Software-Defined Radio(SDR) technique is being actively proceeded instead of traditional hardware-based receiver. The software-based GPS receiver indicates that the signal acquisition and tracking treated by the hardware-based platform are processed as the software technique through a microprocessor. In this paper, GPS software receiver is designed by using SDR technique and then the signal acquisition, tracking, and the navigation message decoding parts are verified through the PC-based simulation. Moreover, the efficient algorithms are developed about the signal acquisition and tracking parts in order to obtain the accurate pseudorange. Finally, the pseudorange is calculated through the relative channel delay received through the different satellite of L1 frequency band. GPS software receiver proposed in this paper will be included in the element of GPS/Galileo complex system of development target and will provide not only the method that verifies the performance for Galileo Sensor Station standard but also usability by providing various debugging environments.

• Journal of Satellite, Information and Communications
• /
• v.6 no.1
• /
• pp.68-74
• /
• 2011

In this paper, we present the enhancement results such as availability and accuracy using the GPS L1 and Galileo E1 signal combination. To enhance the acquisition and tracking performance of signal processing in GNSS receiver. several tracking loops with integrator, discriminator, and loop filter module are applied. Also, this paper presents the performance comparison results between prototype receiver equipped with hardware board and software receiver. Also the tracking loop performance of real hardware receiver is verified by comparing with tracking accuracy, sensitivity occurred by the Spirent simulator. Especially, to process the Galileo E1 signal, it is used the a power early late type which is the typical type for DLL discriminator.

• Journal of Digital Convergence
• /
• v.12 no.12
• /
• pp.257-264
• /
• 2014

Through MCU model, Radio Frequency communication is completed using universal asynchronous receiver and transmitter. The communicatin with PC and MCU is completed using RS-232 cable. At first interconnected communication with PC and MCU is necessary for RF communication because tha UART is based technique for RF communication. Program imbeded in microcontroller unit is ran during RF signal is transmitted to other RF module. Data connected with PC and MCU is transmitted between PC and MCU during PC and MCU is connected.