• Title/Summary/Keyword: carrier-to-noise power ratio

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A Novel Carrier-to-noise Power Ratio Estimation Scheme with Low Complexity for GNSS Receivers (GNSS 수신기를 위한 낮은 복잡도를 갖는 새로운 반송파 대 잡음 전력비 추정기법)

  • Yoo, Seungsoo;Baek, Jeehyeon;Yeom, Dong-Jin;Jee, Gyu-In;Kim, Sun Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.7
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    • pp.767-773
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    • 2014
  • The carrier-to-noise power ratio is a key parameter for determining the reliability of PVT (Position, Velocity, and Time) solutions which are obtained by a GNSS (Global Navigation Satellite System) receiver. It is also used for locking a tracking loop, deciding the re-acquisition process, and processing advanced navigation in the receiver subsystem. The representative carrier-to-noise power ratio estimation schemes are the narrowband-wideband power ratio method (NW), the MM (Moment Method), and Beaulieu's method (BL). The NW scheme is the most classical one for commercial GNSS receivers. It is often used as an authoritative benchmark for assessing carrier-to-noise power estimation schemes. The MM scheme is the least biased solution among them, and the BL scheme is a simpler scheme than the MM scheme. This paper focuses on the less biased estimation with low complexity when the residual phase noise remains, then proposes a novel carrier-to-noise power ratio estimation scheme with low complexity for GNSS receivers. The asymptotic bias of the proposed scheme is derived and compared with others, and the simulation results demonstrate that the complexity of the proposed scheme is lowest among them, while the estimation performance of the proposed scheme is similar to those of the BL and MM schemes in normal and high gained reception environments.

Effects of Radio Interference from Digital Phase Modulation(PSK) System on Analog Frequency Modulation(FM) System (아나로그 주파수변조(FM) 무선통신 시스템에 미치는 디지탈 위상변조(PSK) 무선통신 시스템의 간섭 영향)

  • 조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.8 no.2
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    • pp.63-75
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    • 1983
  • This paper has investigated and discussed the effects of multiple PSK signals upon an wideband FM signal in an intersystem interference environment between analog and digital radios. Using the derived approximate equation for the output haseband interference noise, the signal-to-interference noise power ratio(SNR) in the top channel baseband signal has been numerically calculated. The results are plotted in graphs as the functions of carrier-to-noise ratio(CNR), carrier-to interfer power ratio(CIR), and normalized carrier separation. From the results in this paper, one can know some optimu, or suitable, operating conditions(frequency allocation, bandwidth, and power, etc.) for an FM channel in the intersystemn interferences from digital PSK channels.

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Adaptive Bandwidth Algorithm for Optimal Signal Tracking of DGPS Reference Receivers

  • Park, Sang-Hyun;Cho, Deuk-Jae;Seo, Ki-Yeol;Suh, Sang-Hyun
    • Journal of Navigation and Port Research
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    • v.31 no.9
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    • pp.763-769
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    • 2007
  • A narrow loop noise bandwidth method is desirable to reduce the error of raw measurements due to the thermal noise. However, it degrades the performance of GPS initial synchronization such as mean acquisition time. And it restricts the loop noise bandwidth to a fixed value determined by the lower bound of the allowable range of carrier-to-noise power ratio, so that it is difficult to optimally track GPS signal. In order to make up for the weak points of the fixed-type narrow loop noise bandwidth method and simultaneously minimize the error of code and carrier measurements, this paper proposes a stepwise-type adaptive bandwidth algorithm for DGPS reference receivers. In this paper, it is shown that the proposed adaptive bandwidth algorithm can provide more accurate measurements than those of the fixed-type narrow loop noise bandwidth method, in view of analyzing the simulation results between two signal tracking algorithms. This paper also carries out sensitivity analysis of the proposed adaptive bandwidth algorithm due to the estimation uncertainty of carrier-to-noise power ratio. Finally the analysis results are verified by the experiment using GPS simulator.

Cramer-Rao Lower Bound of Effective Carrier-to-noise Power Ratio Estimation for a GPS L1 C/A Signal under Band-limited White Noise Jamming Environments (대역제한 백색잡음 재밍환경에서 GPS L1 C/A 신호를 위한 유효 반송파 대 잡음 전력비 추정치의 CRLB)

  • Yoo, Seungsoo;Yeom, Dong-Jin;Jee, Gyu-In;Kim, Sun Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.8
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    • pp.890-894
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    • 2014
  • In this paper, we derive the CRLB (Cramer-Rao Lower Bound) of effective carrier-to-noise power ratio ($C/N_0$) estimation for a GPS (Global Positioning System) L1 C/A (Coarse/Acquisition) signal under band-limited white noise jamming environments. The quality of a received GPS signal is commonly described in terms of its $C/N_0$, implying that the noise is white and thus can be described by scalar noise density. However, if some intentional interference is received to a victim GPS receiver, then the $C/N_0$ is no longer the efficacious performance indicator. The correct and straightforward measurement to analyze the receiving situation is the effective $C/N_0$. In this paper, we consider a band-limited white noise jamming whose bandwidth is 2MHz and is the same as one of the first null-to-null bandwidth of the GPS L1 C/A signal.

The Performance Analysis of Multi-Level Quadrature Partial Response Signaling System (다치 직교 Partial Response Signaling 시스템의 특성에 관한 연구)

  • 이광열;고봉진;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.13 no.4
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    • pp.285-301
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    • 1988
  • The symbol error rate equations of multi-level quadrature PRS(QPRS) system have been derived in the individual and composite environment of Gaussian/impulsive noise, cochannel CW interference, carrier offset, phase jitter and fading. And using the derived error rate equations, the probability of error has been evaluated and shown in graphs as functions of carrier to noise power ratio, carrier to interference power ratio, phase error, impulsive index, the ration of Gaussian noise to impulsive noise power component, signal to noise power ration in phase locked loop(PLL), and fading figures. The rseults show that the error rate performances are generally more more degraded by impulsive noise than by Gaussian noise. But on the contrary the erors occurred more frequently by Gaussian noise than impulsive noise in a fading environment.

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A Comparison of C/No Estimation Techniques for Commercial GPS Receivers under Jamming Environments (전파방해환경에서 상용 GPS 수신기의 C/No 추정기법 성능분석)

  • Baek, Jeehyeon;Yoo, Seungsoo;Kim, Sun Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.11
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    • pp.973-975
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    • 2013
  • In this paper, the carrier-to-noise power ratio estimation performances for commercial GPS receiver are shown by simulation and are analyzed under weak signal reception, high sensitivity signal reception, and the matched spectrum jamming signal reception environments.

The Performance of MSK System in Digital Mobile Radio Channels (디지틀 이동 무선통신 회선상에서의 MSK 시스템의 특성)

  • 손승완;조성준
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1984.10a
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    • pp.37-42
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    • 1984
  • In this paper, the error rate equation of MSK system through the Nakagami's m-distribyted fading channel has been derived in the interference and inpulsive noise invironments. The evaluated performances are shown and discussed in terms of carrier-to-noise power ratio, carrier-to-interferer power ratio, fading figure, and impulsive indexes.

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The Analysis of the Effects of Interference and Noise on Land Mobile Radio Communications (이동체 통신에 미치는 제선 간섭잡음의 해석)

  • 손승완;공병옥;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.10 no.3
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    • pp.135-146
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    • 1985
  • The error rate equation of MSK(Minimum Shift Keying) signal transmitted through the fading channel has been derived in the interference and impulsive noise environments. The error rate performance of MSK system have been evaluated and shown in figures as parameters of carrier-to-noise power ratio(CNR), carrier-to-interferer power ratio(CIR), impulsive index, the ratio of Gaussian noise power component to impulsive noise power component, and fading figure. The results show that, in the fading environment, the error is occurred more frequently by Gaussian noise in the deep fading, however in the shallow fading, impulsive noise is more dominant than Gaussian noise. And in thepresence of interference and fading, interferer deteriorates the MSK receiving system severely even if the interferer is weak.

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Conducted Noise Reduction in Three-Phase Boost Converter using Random (3상 승압형 컨버터에 의한 전도노이즈 감소)

  • Jung, Dong-Hyo;Kim, Sang-Nam
    • Proceedings of the KIEE Conference
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    • 2003.07e
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    • pp.79-82
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    • 2003
  • The switching-mode power converter has been widely used because of its features of high efficiency and small weight and size. In the switching-mode power converter, the output voltage is generally controlled by varying the duty ratio of main switch. When a converter operates in steady state, duty ratio of the converter is kept constant. So the power of switching noise is concentrated in specific frequencies. The more white noise is injected, the more conducted EMI is reduced. But output-voltage is not sufficiently regulated. This is the reason why carrier frequency selection topology is proposed. In the case of carrier frequency selection, output-voltage of steady state and transient state is fully regulated. Spectrum analysis is performed on the Phase current and the CM noise voltage. The former is measured with Current Probe and the latter is achieved with LISN, which are connected to the spectrum analyzer respectively.

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A Study for the Error Performance in 16 Quadrature Amplitude Modulation System (간섭 및 잡음에 대한 16상직교진 폭변조시스템의 오율분석)

  • 박경호;박석철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.12 no.3
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    • pp.204-215
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    • 1987
  • In this paper, 16QAM techniques are described. The evaluated error rate performences are shown in figures as parameters of carrier-to-noise power ratio(CNR), carrier-to-interference power ratio(CIR), impulsive noise index, and Gaussian to impulsive noise power ration. Also, the error rate performances are measured experimentally by hardware system and compared with the theoretical results.

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