A Novel Signal Design and Performance Analysis in NavCom Based on LEO Constellation

The mega-launch of low Earth orbit satellites (LEOs) represents a critical opportunity to integrate navigation and communication (NavCom), but first, challenges related to signal design must be overcome. This article proposes a novel signal scheme named CE-OFDM-PM. Via research on the in-band or adjacent band, it was found that the proposed signal scheme was suitable for S-band and had a wide normalized power spectrum density (PSD), high peak-to-side lobe ratio (PSR), and multiple peaks in autocorrelation. In an analysis of the simulation performance evaluation in navigation and communication, it is found that the proposed signal scheme has the potential for high accuracy, a code tracking accuracy of up to 0.85 m, a small mutual influence between the proposed signal scheme and other schemes, excellent anti-interference properties, and a better performance at both short and long distances in terms of its anti-multipath capability. Furthermore, the proposed signal scheme shows the ability to communicate between satellites and the ground and is outstanding in terms of its bit error rate (BER), CNR, and energy per bit to noise power spectral density ratio (Eb/N0). From the technical, theoretical, and application perspectives, our proposed signal scheme has potential as an alternative scheme in future BDS, PNTs, and even 5G/B5G.

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Robustness against Chirp Signal Interference of On-Board Vehicle Geodetic and Low-Cost GNSS Receivers

Sensors ◽

10.3390/s21165257 ◽

2021 ◽

Vol 21 (16) ◽

pp. 5257

Author(s):

Franc Dimc ◽

Polona Pavlovčič-Prešeren ◽

Matej Bažec

Keyword(s):

Interference Mitigation ◽

Low Cost ◽

Density Ratio ◽

Autonomous Driving ◽

Signal Interference ◽

Noise Power ◽

Reference Base ◽

Noise Power Spectral Density ◽

Processing Abilities ◽

Gnss Receivers

Robust autonomous driving, as long as it relies on satellite-based positioning, requires carrier-phase-based algorithms, among other types of data sources, to obtain precise and true positions, which is also primarily true for the use of GNSS geodetic receivers, but also increasingly true for mass-market devices. The experiment was conducted under line-of-sight conditions on a straight road during a period of no traffic. The receivers were positioned on the roof of a car travelling at low speed in the presence of a static jammer, while kinematic relative positioning was performed with the static reference base receiver. Interference mitigation techniques in the GNSS receivers used, which were unknown to the authors, were compared using (a) the observed carrier-to-noise power spectral density ratio as an indication of the receivers’ ability to improve signal quality, and (b) the post-processed position solutions based on RINEX-formatted data. The observed carrier-to-noise density generally exerts the expected dependencies and leaves space for comparisons of applied processing abilities in the receivers, while conclusions on the output data results comparison are limited due to the non-synchronized clocks of the receivers. According to our current and previous results, none of the GNSS receivers used in the experiments employs an effective type of complete mitigation technique adapted to the chirp jammer.

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Analisis Unjuk Kerja Convolutional Code pada Sistem MIMO MC-DSSS Melalui Kanal Rayleigh Fading

Majalah Ilmiah Teknologi Elektro ◽

10.24843/mite.2017.v16i02p11 ◽

2017 ◽

Vol 16 (2) ◽

pp. 66 ◽

Cited By ~ 1

Author(s):

Kadek Agus Mahabojana Dwi Prayoga ◽

Ni Made Ary Esta Dewi Wirastuti ◽

I Gst A. Komang Diafari Djuni Hartawan

Keyword(s):

Spread Spectrum ◽

Orthogonal Frequency Division Multiplexing ◽

Rayleigh Fading ◽

Convolutional Code ◽

Multiple Input Multiple Output ◽

Density Ratio ◽

Direct Sequence Spread Spectrum ◽

Noise Power ◽

Noise Power Spectral Density ◽

Input Multiple Output

Kombinasi antara sistem MIMO (multiple input multiple output), OFDM (orthogonal frequency division multiplexing), dan spread spectrum serta adanya teknik pengkodean kanal mampu mengurangi efek fading dan error yang terjadi. Penelitian ini bertujuan untuk mengetahui perbandingan performansi dari sistem MIMO MC-DSSS (multi carrier-direct sequence spread spectrum) Uncoded atau tanpa pengkodean kanal dan MIMO MC-DSSS Convolutional Code atau dengan pengkodean kanal Convolutional yang melalui kanal Rayleigh Fading, ditinjau dari nilai dan grafik BER (bit error rate) berbanding Eb/No (energy per bit to noise power spectral density ratio). Penelitian ini menggunakan metode simulasi dengan menggunakan program Matlab R2015a. Hasil dari simulasi didapat unjuk kerja sistem MIMO MC-DSSS dengan Convolutional Code memiliki hasil yang lebih baik dari MIMO MC-DSSS. Pada kanal transmisi Rayleigh Fading untuk mencapi nilai BER sebesar 10-3 pada sistem MIMO MC-DSSS dengan Convolutional Code dibutuhkan Eb/No sebesar -7 dB. Sedangkan pada sistem MIMO MC-DSSS dibutuhkan Eb/No sebesar -3 dB.[turnitin 20%, 7-11-2016]

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Evaluaciónde OPS para la Reducción de la PAPR en un SistemaOFDM conCanal Multitrayecto

Revista Politécnica ◽

10.33333/rp.vol44n2.04 ◽

2020 ◽

Vol 44 (2) ◽

pp. 35-42

Author(s):

María Peñaherrera ◽

Diego Reinoso

Keyword(s):

Bit Error Rate ◽

Orthogonal Frequency Division Multiplexing ◽

Density Ratio ◽

Average Power ◽

Noise Power ◽

Power Ratio ◽

Frequency Division ◽

Complementary Distribution ◽

Noise Power Spectral Density ◽

Power Spectral

OFDM (Orthogonal Frequency Division Multiplexing) es una tecnología de comunicacióninalámbrica que tiene ventajas como alta eficiencia espectral, alta tasa de transmisión y es robusta a la propagación por mulitrayecto. Sin embargo, su principal desventaja es que tienealta PAPR (Peak-to-Average Power Ratio).Este artículo presenta la evaluaciónde la técnica OPS (Orthogonal Pilot Sequence) para la reducción de la PAPR en un sistema OFDM con canal multitrayecto. Para la evaluación se consideran dos tipos de canalesmultitrayecto selectivos en frecuencia, con y sin línea de vista. Se evalúa la técnica OPS obteniendola gráfica del BER (Bit Error Rate)vs Eb/No (energy per bit to noise power spectral density ratio) y la gráfica de la CCDF (Cumulative Complementary Distribution Function) para distintos parámetros. Losresultados muestran una reducción de la PAPR cuando se utiliza la técnica OPS y una mejora en el BER.

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LEO-Augmented GNSS Based on Communication Navigation Integrated Signal

Sensors ◽

10.3390/s19214700 ◽

2019 ◽

Vol 19 (21) ◽

pp. 4700 ◽

Cited By ~ 1

Author(s):

Lei Wang ◽

Zhicheng Lü ◽

Xiaomei Tang ◽

Ke Zhang ◽

Feixue Wang

Keyword(s):

Satellite System ◽

High Accuracy ◽

Good Choice ◽

Low Earth Orbit ◽

Noise Power ◽

Communication Performance ◽

Noise Power Spectral Density ◽

Communication Signal ◽

Navigation Signal ◽

Global Navigation Satellite

Low Earth Orbit (LEO) is of great benefit for the positioning performance of Global Navigation Satellite System (GNSS). To realize the system of LEO-augmented GNSS, three methods to integrate communication and navigation signal for LEO communication system with the least influence on the communication performance are analyzed. The analysis adopts the parameters of IRIDIUM signal as restrictions. This paper gives quantitative comparison of these methods considering CN0(carrier noise power spectral density rate) margin, pseudorange accuracy, Doppler accuracy, and communication loss. For method 1, a low-power navigation signal is added to the communication signal. For method 2, the navigation signal is launched in one or more frames. For method 3, the navigation signal is launched in the frequency band separated to the communication signal. The result shows that the pseudorange accuracy of method 2 is far below method 1 and method 3. However, the difference of Doppler accuracy among the three methods can be emitted. Detailed analysis shows that method 1 is practicable when the communication and navigation signal power rate is 15 dB. It achieves the balance of pseudorange accuracy and bit error rate (BER) performance under this condition. Comprehensive comparison of these methods is given in the last. The result shows that the CN0 margin of the navigation signal for method 3 can be 13.04 dB higher than method 1, based on the accuracy threshold considered in this paper. Methods 1 and 3 have the advantage of high accuracy and high CN0 margin respectively. However, method 3 causes high communication capacity loss. Considering that the main disadvantage of GNSS signals is low CN0, method 3 is a good choice for the LEO-augmented GNSS system. Methods 1 and 3 can be combined to realize both high accuracy and high CN0 margin if possible.

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Analisis Unjuk Kerja Improved Sinc Power Pulse pada Sistem OFDM Melalui Kanal Frequency Selective Fading

Majalah Ilmiah Teknologi Elektro ◽

10.24843/mite.2019.v18i03.p04 ◽

2019 ◽

Vol 18 (3) ◽

pp. 323

Author(s):

Kadek Agus Mahabojana Dwi Prayoga ◽

NMAE Dewi Wirastuti ◽

Nyoman Pramaita

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Pulse Shaping ◽

Density Ratio ◽

Pulse Frequency ◽

Noise Power ◽

Selective Fading ◽

Frequency Selective Fading ◽

Power Pulse ◽

Noise Power Spectral Density ◽

Frequency Selective

Kombinasi antara sistem OFDM (orthogonal frequency division multiplexing) dan Pulse Shaping mampu mengurangi Inter Carrier Interference (ICI) dan error yang terjadi. Penelitian ini bertujuan untuk mengetahui perbandingan performansi dari sistem OFDM tanpa pulse shaping dan OFDM dengan pulse shaping Improved Sinc Power (ISP) pulse yang melalui kanal Frequency Selective Fading, ditinjau dari BER (bit error rate) berbanding Eb/No (energy per bit to noise power spectral density ratio). Penelitian ini menggunakan metode simulasi dengan menggunakan program Matlab R2018a. Hasil dari simulasi didapat unjuk kerja sistem OFDM dengan pulse shaping ISP pulsememiliki hasil yang lebih baik dari OFDM tanpa pulse shaping. Pada kanal transmisi Frequency Selective Fading untuk mencapi nilai BER sebesar 10-1 sistem OFDM dengan pulse shaping ISP pulse dibutuhkan Eb/No sebesar 2 dB. Sedangkan pada sistem OFDM tanpa pulse shaping dibutuhkan Eb/No sebesar 10 dB. Kata Kunci — OFDM, Pulse Shaping, ICI, ISP pulse, Frequency Selective Fading.

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Analytical Models for the Computation of Error Probability of Multi-Level Phase Shift Keying Modulation Scheme

British Journal of Computer, Networking and Information Technology ◽

10.52589/bjcnit-lsfcmvli ◽

2021 ◽

Vol 4 (1) ◽

pp. 13-20

Author(s):

Isaac A. E. ◽

Dike H.U.

Keyword(s):

Phase Shift ◽

Error Probability ◽

Error Function ◽

Density Ratio ◽

Analytical Models ◽

Modulation Scheme ◽

Noise Power ◽

Phase Shift Keying ◽

Shift Keying ◽

Multi Level

In this paper, analytical models for the computation of error probability (BER) of the Multi-level Phase Shift Keying (MPSK) modulation scheme is presented. Analytical models for computing MPSK bit error probability based on Q function, error function (erf) and complementary error function (erfc) are presented. Also, an analytical model for computing the symbol error rate for MPSK is presented. Furthermore, a generalized analytical expression for BER as a function of modulation order (M) and energy per bit to noise power density ratio (Eb/No) is presented. The BER was computed for various values of M (2 ≤ M ≤ 256) and Eb/No (0 dB ≤ Eb/No ≤ 14 Db). The results showed that at Eb/No =12 dB, a BER of 9.006E-09 is realized for M =2 and M =4 whereas BER of 1.056E-01 is realized for M = 256. Also, for the same M = 2 , the value of BER decreased from 1.2501E-02 at Eb/No = 4 dB to 9.0060E-09at Eb/No =12 dB. Generally, the results showed that for the MPSK modulation scheme, for a given value of Eb/No, the lower modulation order (M) has a lower BER and for a given modulation order, (M) the BER decreases as Eb/No increases.

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Visible Light Communication System Based on Software Defined Radio: Performance Study of Intelligent Transportation and Indoor Applications

Electronics ◽

10.3390/electronics8040433 ◽

2019 ◽

Vol 8 (4) ◽

pp. 433 ◽

Cited By ~ 12

Author(s):

Radek Martinek ◽

Lukas Danys ◽

Rene Jaros

Keyword(s):

Visible Light ◽

Communication System ◽

Software Defined Radio ◽

Density Ratio ◽

Visible Light Communication ◽

Noise Power ◽

Error Vector Magnitude ◽

Performance Study ◽

Variable Nature ◽

Ceiling Light

In this paper, our first attempt at visible light communication system, based on software defined radio (SDR) and implemented in LabVIEW is introduced. This paper mainly focuses on two most commonly used types of LED lights, ceiling lights and LED car lamps/tail-lights. The primary focus of this study is to determine the basic parameters of real implementation of visible light communication (VLC) system, such as transmit speed, communication errors (bit-error ratio, error vector magnitude, energy per bit to noise power spectral density ratio) and highest reachable distance. This work focuses on testing various multistate quadrature amplitude modulation (M-QAM). We have used Skoda Octavia III tail-light and Phillips indoor ceiling light as transmitters and SI PIN Thorlabs photodetector as receiver. Testing method for each light was different. When testing ceiling light, we have focused on reachable distance for each M-QAM variant. On the other side, Octavia tail-light was tested in variable nature conditions (such as thermal turbulence, rain, fog) simulated in special testing box. This work will present our solution, measured parameters and possible weak spots, which will be adjusted in the future.

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