• Journal of Positioning, Navigation, and Timing
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• v.4 no.1
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• pp.9-16
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• 2015

The applications of Global Navigation Satellite System (GNSS) receivers are becoming wider in various commercial and military systems including even small weapon systems such as artillery shells. The precision-guided munitions such as Small Diameter Bomb (SDB) of United States can be used for pinpoint strike by acquiring and tracking GNSS signals in high mobility situation. In this paper, a small GNSS receiver with embedded interference suppression capability working under high dynamic stress is developed which is applicable to the various weapon systems and can be used in other several harsh environments. It applies a kind of matched filter and multiple correlator schemes for fast signal acquisition and tracking of even weak signals and frequency domain signal processing method to eliminate the narrowband interference. To evaluate the performance of the developed GNSS receiver, the test scenario of high mobility and interference environment with the GNSS simulator and signal generator is devised. Then, the signal acquisition time, navigation accuracy, sensitivity, and interference suppression performances under high dynamic operation are evaluated. And the comparison test with the commercial GNSS receiver which has high sensitivity is made under the same test condition.

• Journal of Positioning, Navigation, and Timing
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• v.7 no.4
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• pp.189-203
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• 2018

In this paper, a Software Defined Radio (SDR) architecture was designed and implemented for rapid prototyping of GNSS receiver. The proposed SDR can receive various GNSS and direct sequence spread spectrum (DSSS) signals without software modification by expanded input parameters containing information of the desired signal. Input parameters include code information, center frequency, message format, etc. To receive various signal by parameter controlling, a correlator, a data bit extractor and a receiver channel were designed considering the expanded input parameters. In navigation signal processing, pseudorange was measured based on Coordinated Universal Time (UTC) and appropriate navigation message decoder was selected by message format of input parameter so that receiver position can be calculated even if SDR is set up various GNSS combination. To validate the proposed SDR, the software was implemented using C++, CUDA C based on GPU and USRP. Experimentation has confirmed that changing the input parameters allows GPS, GLONASS, and BDS satellite signals to be received. The precision of the position from implemented SDR were measured below 5 m (Circular Error Probability; CEP) for all scenarios. This means that the implemented SDR operated normally. The implemented SDR will be used in a variety of fields by allowing prototyping of various GNSS signal only by changing input parameters.

• Journal of Navigation and Port Research
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• v.29 no.10 s.106
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• pp.877-882
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• 2005

It is necessary that Fail-Safe Seaway technology providing a continuous navigation solution though fault of navigation system is occurred in sea. This paper focus on signal processing of GPS receiver, one of receivers using the software radio technology to implement a integrated radio navigation system including satellite-based and ground-based navigation systems. It is difficult to implement the software GPS receivers using a commercial processor because of the heavy computational burden for processing the GPS signals in real time. This paper proposes an efficient multi-bit GPS signal processing scheme to reduce the computational burden for processing the GPS signals in the software GPS receiver. The proposed scheme uses a compression concept of the multi-bit replica signals and patterned look-up table method to generate the correlation value between the GPS signals and the replica signals.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.37-42
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• 2005

It is necessary that Fail-Safe Seaway technology providing a continuous navigation solution though fault of navigation system is occurred in sea. This paper focus on signal processing of GPS receiver, one of receivers using the software radio technology to implement a integrated radio navigation system including satellite-based and ground-based navigation systems. It is difficult to implement the software GPS receivers using a commercial processor bemuse of the heavy computational burden for processing the GPS signals in real time. This paper proposes an efficient multi-bit GPS signal processing scheme to reduce the computational burden for processing the GPS signals in the software GPS receiver. The proposed scheme uses a compression concept of the multi-bit replica signals and patterned look-up table method to generate the correlation value between the GPS signals and the replica signals.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.9
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• pp.1069-1080
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• 2016

TDOA(Time Difference Of Arrival)-based localization system such as the passive surveillance system performs the time synchronization between the receivers after separated installing multiple receivers to set the same clock for all receivers. And it estimates 2D(or 3D) location of the target by solving intersection of the multiple hyperbola(or hyperboloid) using TDOA. To perform time synchronization, one receiver must be set to the master, and it provide the reference data to compensate the clock of the rest of the slaves. The positioning accuracy of TDOA-based localization system is changed in accordance with the master that is selected among multiple receivers. So, the optimum receiver which is selected among multiple receivers must be set to master to get best performance in the considered deployment of receivers. In this paper, we propose a selection scheme of master receiver for time synchronization using DOP(Dilution Of Precision) which is based on location of the target and the multiple receivers. The proposed scheme has low complexity and short processing time, and it is easy to automate in the TDOA-based localization systems.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.4
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• pp.296-301
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• 2016

Using high magnetic flux from a 60 Hz high-current cable, a 2 W wireless-powered energy harvesting receiver for sensor operation, internet of things (IoT) devices, and LED lights inside electrical cable tunnels is proposed. The proposed receiver comprises a copper coil with a high number of turns, a ring-shaped ferromagnetic core, a capacitor for compensating for the impedance of the coil in series, and a rectifier with various types of loads, such as sensors, IoT devices, and LEDs. To achieve safe and easy installation around the power cable, the proposed ring-shaped receiver is designed to easily open or close using a clothespin-shaped handle, which is made of highly-insulated plastic. Laminated silicon steel plates are assembled and used as the core because of their mechanical robustness and high saturation flux density characteristic, in which the thickness of each isolated plate is 0.3 mm. The series-connected resonant capacitor, which is appropriate for low-voltage applications, is used together with the proposed receiver coil. The concept of the figure of merit, which is the product weight and cost of both the silicon steel plate and the copper wire, is used for an optimized design; therefore, the weight of the fabricated receiver and the price of raw material is 750 gf and USD $2 each, respectively. The 2.2 W powering capability of the fabricated receiver was experimentally verified with a power cable current of $100A_{rms}$ at 60Hz.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9A
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• pp.867-875
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• 2005

In this paper, we fabricated along distance wireless communication transmitter and receiver over the 100 which used NRD technology. To make the transmitter and receiver of 400Hz band using the non radiative dielectric wave guide, transmitter was composed of gm oscillator, m modulator and antenna, receiver was composed of local gum oscillator, balanced mixer, 3dB direction coupler and antenna. Also we executed a wireless communication image transmission examination to the transmitter and receiver. We receive the image information in real-time data transmission from receiver after we send the image signal in the wireless distance of the 10km. Therefore, the 400Hz band U transmitter and receiver to be developed will be used widely for the transmission system CATV or broadband transmission system. This will be utilized also to the link device of a long distance high speed wireless communication network.

• The Bulletin of The Korean Astronomical Society
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• v.18
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• pp.4.2-5
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• 1993

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.440-442
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• 2006

This rarer is to design a low cost GPS/DGPS receiver using GP2021 correlator. By modifying the existent GPS, the performance can be enhance than before. The H/W and S/W should be updated to have good result.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2173-2175
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• 2004

This paper addresses a telemetering device which uses RF transceivers and a mobile-phone. Locally collected data arc encoded with a BCH error correcting code and transferred to a receiver through a RF module. The receiver-side RF module decodes the transferred data and then repetes them to a mobile-phone. Lastly, the mobile-phone hands over the data through a wireless phone network to a host computer in the internet.