Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Positioning, Navigation, and Timing
Journal Basic Information
Journal DOI :
The Korean GNSS Society
Editor in Chief :
Volume & Issues
Volume 3, Issue 4 - Dec 2014
Volume 3, Issue 3 - Sep 2014
Volume 3, Issue 2 - Jun 2014
Volume 3, Issue 1 - Mar 2014
Selecting the target year
Performance Analysis of Pseudorange Error in STAP Beamforming Algorithm for Array Antenna
Lee, Kihoon ; So, Hyungmin ; Song, Kiwon ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 37~44
DOI : 10.11003/JPNT.2014.3.2.037
The most effective method to overcome GPS jamming problem is to use an adaptive array antenna which has the capability of beamforming or nulling to a certain direction. In this paper, Space Time Adaptive Processing (STAP) beamforming algorithm of four elements array antenna will be designed and the anti-jamming performance will be analyzed. According to the analysis, the signal to noise ratio (SNR) and anti-jamming performance can be enhanced by beamforming algorithm. Also, the time tap effect of STAP algorithm will be analyzed theoretically and verified with array antenna modeling and simulation. Specially, the cautious selection of reference time tap in STAP can prevent the degradation of position accuracy performance.
Jammer Identification Technique based on a Template Matching Method
Jin, Mi Hyun ; Yeo, Sang-Rae ; Choi, Heon Ho ; Park, Chansik ; Lee, Sang Jeong ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 45~51
DOI : 10.11003/JPNT.2014.3.2.045
GNSS has the disadvantage of being vulnerable to jamming, and thus, the necessity of jamming countermeasure techniques has gradually increased. Jamming countermeasure techniques can be divided into an anti-jamming technique and a jammer localization technique. Depending on the type of a jammer, applicable techniques and performance vary significantly. Using an appropriate jamming countermeasure technique, the effect of jamming on a GNSS receiver can be attenuated, and prompt action is enabled when estimating the location of a jammer. However, if an inappropriate jamming countermeasure technique is used, a GNSS receiver may not operate in the worst case. Therefore, jammer identification is a technique that is essential for proper action. In this study, a technique that identifies a jammer based on template matching was proposed. For template matching, analysis of a received jamming signal is required; and the signal analysis was performed using a spectral correlation function. Based on a simulation, it was shown that the proposed identification of jamming signals was possible at various JNR.
Development of MEMS-IMU/GPS Integrated Navigation System
Kim, Jeong Won ; Nam, Chang Woo ; Lee, Jae-Cheul ; Yoon, Sung Jin ; Rhim, Jaewook ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 53~62
DOI : 10.11003/JPNT.2014.3.2.053
In the guided missile and unmanned vehicle system, the navigation system is one of the most important components. Recently, low-cost effective smart projectiles and guided bomb are being developed using MEMS based navigation system which has high-G, low-cost and small size. In this paper, locally developed MEMS based GPS/INS integrated navigation system will be introduced in comparison with the state of the art of MEMS based navigation system. And technical design and development method is described to satisfy the required performance of GPS receiver, MEMS inertial sensor assembly, navigation computer and software.
Design of an Array Antenna Hood for Jamming Simulator
Kim, Mi-Suk ; Ju, Jeong-Gab ; Kim, Jong Seong ; Son, Seok Bo ; Yun, Sang Jun ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 63~69
DOI : 10.11003/JPNT.2014.3.2.063
In this study, due to the necessity of the equipment for inspecting an anti-jamming function depending on the expansion of the development of anti-jamming systems, an array antenna hood that can inspect the anti-jamming function of an anti-jamming system while being installed at the system was designed and manufactured. The manufactured array antenna hood plays a role in radiating GNSS signals and jamming signals. Based on an experiment, it was demonstrated that using a near-field radiation method, the manufactured array antenna hood could be used for examining the normal operation of an anti-jamming system function in outdoor or indoor environments rather than an anechoic chamber.
A Design of Dual Frequency Bands Time Synchronization System for Synchronized-Pseudolite Navigation System
Seo, Seungwoo ; Park, Junpyo ; Suk, Jin-Young ; Song, Kiwon ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 71~81
DOI : 10.11003/JPNT.2014.3.2.071
Time synchronization system using dual frequency bands is designed and the error sources are analyzed for alternative synchronized-pseudolite navigation system (S-PNS) which aims at military application. To resolve near/far problem, dual frequency band operation is proposed instead of pulsing transmission which degrades level of reception. In dual frequency operation H/W delay should be considered to eliminate errors caused by inter-frequency bias (IFB) difference between the receivers of the pseudolites and users. When time synchronization is performed across the sea, multipath error is occurred severely since the elevation angle between pseudolites is low so total reflection can be happened. To investigate the difference of multipath effects according to location, pseudolites are set up coastal area and land area and performances are compared. The error source related with tropospheric delay is becoming dominant source as the coverage of the PNS is broadening. The tropospheric delay is measured by master pseudolite receiver directly using own pseudorange and slave pseudorange. Flight test is performed near coastal area using S-PNS equipped with developed time synchronization system and test results are also presented.
A Study on the Field Strength Prediction of a Ground-wave Based Time Broadcasting Transmitter Station in the Korean Peninsula
Lee, Sun Yong ; Choi, Yun Sub ; Hwang, Sang-Wook ; Yang, Sung-Hoon ; Lee, Chang-Bok ; Lee, Sang Jeong ;
Journal of Positioning, Navigation, and Timing, volume 3, issue 2, 2014, Pages 83~90
DOI : 10.11003/JPNT.2014.3.2.083
In this study, to improve an existing ground-wave based time broadcasting system, a study that predicts the field distribution and field strength of the transmitted signal of a new ground-wave based time broadcasting system was performed. The prediction area was assumed to be the Korean peninsula; and to reflect the mountainous terrain of the Korean peninsula in the prediction of the variations of field distribution and field strength, a new prediction method based on the Monteath model was proposed and utilized. As field distribution changes depending on the position of a transmitter station, potential sites for the transmitter station were selected considering the geographical characteristics. In this regard, the ground conductivity information of North Korea cannot be obtained, and thus, the ground conductivity of the North Korean region was reflected considering the geological characteristics of South Korea and North Korea. Based on this, the variations of field distribution and field strength were predicted by setting the Korean peninsula as the prediction area, and the prediction results depending on the position of the transmitter station were discussed.