AF cooperative VLC communication systems : cascaded channel analysis
- Ndjiongue, A. R., Ngatched, Telex M. N., Ferreira, Hendrik C.
- Authors: Ndjiongue, A. R. , Ngatched, Telex M. N. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Cascaded VLC system , Amplify-and-forward strategy , Relay-assisted VLC system
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/294522 , uj:32048 , Citation: Ndjiongue, A.R., Ngatched, T.M.N. & Ferreira, H.C. 2019. AF cooperative VLC communication systems : cascaded channel analysis.
- Description: Abstract: Visible light communications (VLC) technology is a relatively new emerging telecommunication paradigm. It offers the opportunity to design cost-effective communication systems due to the dual use of the light sources, which are exploited as illumination devices and as communication antennas. However, this technology is mostly deployed in short-range communication applications because of the light diffusion range, which is short by nature. One good response to this dilemma is the imple- mentation of relay-assisted cooperative communication systems. Cooperative VLC systems provide three advantages, which are an increase in the transmission range, an improvement of the detection, hence of the bit error rate (BER), and an improved lighting system. In this paper, we analyze the channel response of a single-relay indoor VLC system based on an amplify-and- forward (AF) strategy. The system takes into account the fact that the relay also receives a reflected message. Results show the influence of the room’s reflection index, Lambertian index, the number of scattered rays on the overall channel response and confirms the importance of relay-assisted strategies in improving systems’ reliability.
- Full Text:
- Authors: Ndjiongue, A. R. , Ngatched, Telex M. N. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Cascaded VLC system , Amplify-and-forward strategy , Relay-assisted VLC system
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/294522 , uj:32048 , Citation: Ndjiongue, A.R., Ngatched, T.M.N. & Ferreira, H.C. 2019. AF cooperative VLC communication systems : cascaded channel analysis.
- Description: Abstract: Visible light communications (VLC) technology is a relatively new emerging telecommunication paradigm. It offers the opportunity to design cost-effective communication systems due to the dual use of the light sources, which are exploited as illumination devices and as communication antennas. However, this technology is mostly deployed in short-range communication applications because of the light diffusion range, which is short by nature. One good response to this dilemma is the imple- mentation of relay-assisted cooperative communication systems. Cooperative VLC systems provide three advantages, which are an increase in the transmission range, an improvement of the detection, hence of the bit error rate (BER), and an improved lighting system. In this paper, we analyze the channel response of a single-relay indoor VLC system based on an amplify-and- forward (AF) strategy. The system takes into account the fact that the relay also receives a reflected message. Results show the influence of the room’s reflection index, Lambertian index, the number of scattered rays on the overall channel response and confirms the importance of relay-assisted strategies in improving systems’ reliability.
- Full Text:
Binary balanced codes approaching capacity
- Esenogho, Ebenezer, Mambou, Elie N., Swart, Theo G., Ferreira, Hendrik C.
- Authors: Esenogho, Ebenezer , Mambou, Elie N. , Swart, Theo G. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced codes , Redundancy , Binary alphabet
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/401121 , uj:33508 , Citation: Esenogho, E. et al. 2019. Binary balanced codes approaching capacity.
- Description: Abstract: In this paper, the construction of binary balanced codes is revisited. Binary balanced codes refer to sets of bipolar codewords where the number of “1”s in each codeword equals that of “0”s. The first algorithm for balancing codes was proposed by Knuth in 1986; however, its redundancy is almost two times larger than that of the full set of balanced codewords. We will present an efficient and simple construction with a redundancy approaching the minimal achievable one.
- Full Text:
- Authors: Esenogho, Ebenezer , Mambou, Elie N. , Swart, Theo G. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced codes , Redundancy , Binary alphabet
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/401121 , uj:33508 , Citation: Esenogho, E. et al. 2019. Binary balanced codes approaching capacity.
- Description: Abstract: In this paper, the construction of binary balanced codes is revisited. Binary balanced codes refer to sets of bipolar codewords where the number of “1”s in each codeword equals that of “0”s. The first algorithm for balancing codes was proposed by Knuth in 1986; however, its redundancy is almost two times larger than that of the full set of balanced codewords. We will present an efficient and simple construction with a redundancy approaching the minimal achievable one.
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Improving the redundancy of Knuth’s balancing scheme for packet transmission systems
- Ngomseu Mambou, Elie, Esenogho, Ebenezer, Ferreira, Hendrik C.
- Authors: Ngomseu Mambou, Elie , Esenogho, Ebenezer , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced codes , Binary word , Parallel decoding
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/398841 , uj:33221 , Citation: Ngomseu M.E., Esenogho, E. & Ferreira, H. 2019. Improving the redundancy of Knuth’s balancing scheme for packet transmission systems. Turkish Journal of Electrical Engineering & Computer Sciences.
- Description: Abstract: A simple scheme was proposed by Knuth to generate binary balanced codewords from any information word. However, this method is limited in the sense that its redundancy is twice that of the full sets of balanced codes. The gap between Knuth’s algorithm’s redundancy and that of the full sets of balanced codes is significantly considerable. This paper attempts to reduce that gap. Furthermore, many constructions assume that a full balancing can be performed without showing the steps. A full balancing refers to the overall balancing of the encoded information together with the prefix. We propose an efficient way to perform a full balancing scheme that does not make use of lookup tables or enumerative coding.
- Full Text:
- Authors: Ngomseu Mambou, Elie , Esenogho, Ebenezer , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced codes , Binary word , Parallel decoding
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/398841 , uj:33221 , Citation: Ngomseu M.E., Esenogho, E. & Ferreira, H. 2019. Improving the redundancy of Knuth’s balancing scheme for packet transmission systems. Turkish Journal of Electrical Engineering & Computer Sciences.
- Description: Abstract: A simple scheme was proposed by Knuth to generate binary balanced codewords from any information word. However, this method is limited in the sense that its redundancy is twice that of the full sets of balanced codes. The gap between Knuth’s algorithm’s redundancy and that of the full sets of balanced codes is significantly considerable. This paper attempts to reduce that gap. Furthermore, many constructions assume that a full balancing can be performed without showing the steps. A full balancing refers to the overall balancing of the encoded information together with the prefix. We propose an efficient way to perform a full balancing scheme that does not make use of lookup tables or enumerative coding.
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Mathematical approach and implementation of frequency mapping techniques in power-line communications channel
- Lukusa, Tedy, Ouahada, Khamaies, Ferreira, Hendrik C.
- Authors: Lukusa, Tedy , Ouahada, Khamaies , Ferreira, Hendrik C.
- Date: 2019
- Subjects: M -FSK Modulation , Power-Line Communications , Viterbi Decoder
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/404663 , uj:33947 , Lukusa, T., Ouahada, K., Ferreira, H.C. 2019: Mathematical approach and implementation of frequency mapping techniques in power-line communications channel : Commun. Appl. Ind. Math. 10 (1), 2019, 88–108 : DOI: 10.2478/caim-2019-0015
- Description: Abstract : Please refer to full text to view abstract.
- Full Text:
- Authors: Lukusa, Tedy , Ouahada, Khamaies , Ferreira, Hendrik C.
- Date: 2019
- Subjects: M -FSK Modulation , Power-Line Communications , Viterbi Decoder
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/404663 , uj:33947 , Lukusa, T., Ouahada, K., Ferreira, H.C. 2019: Mathematical approach and implementation of frequency mapping techniques in power-line communications channel : Commun. Appl. Ind. Math. 10 (1), 2019, 88–108 : DOI: 10.2478/caim-2019-0015
- Description: Abstract : Please refer to full text to view abstract.
- Full Text:
New distance concept and graph theory approach for certain coding techniques design and analysis
- Ouahada, Khmaies, Ferreira, Hendrik C.
- Authors: Ouahada, Khmaies , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Graph theory , Distance mappings , Spectral codes
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/404135 , uj:33880 , Citation: Ouahada, K. & Ferreira, H.C. 2019. Communications in Applied and Industrial Mathematics, 10(1):1–18. DOI: 10.1515/caim-2019-0XXX
- Description: Abstract: A New graph distance concept introduced for certain coding techniques helped in their design and analysis as in the case of distance-preserving mappings and spectral shaping codes. A graph theoretic construction, mapping binary sequences to permutation sequences and inspired from the k-cube graph has reached the upper bound on the sum of the distances for certain values of the length of the permutation sequence. The new introduced distance concept in the k-cube graph helped better understanding and analyzing for the first time the concept of distance-reducing mappings. A combination of distance and the index-permutation graph concepts helped uncover and verify certain properties of spectral null codes, which were previously difficult to analyze.
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- Authors: Ouahada, Khmaies , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Graph theory , Distance mappings , Spectral codes
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/404135 , uj:33880 , Citation: Ouahada, K. & Ferreira, H.C. 2019. Communications in Applied and Industrial Mathematics, 10(1):1–18. DOI: 10.1515/caim-2019-0XXX
- Description: Abstract: A New graph distance concept introduced for certain coding techniques helped in their design and analysis as in the case of distance-preserving mappings and spectral shaping codes. A graph theoretic construction, mapping binary sequences to permutation sequences and inspired from the k-cube graph has reached the upper bound on the sum of the distances for certain values of the length of the permutation sequence. The new introduced distance concept in the k-cube graph helped better understanding and analyzing for the first time the concept of distance-reducing mappings. A combination of distance and the index-permutation graph concepts helped uncover and verify certain properties of spectral null codes, which were previously difficult to analyze.
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On the improvement of the Knuth’s redundancy algorithm for balancing codes
- Esenogho, Ebenezer, Mambou, Elie N., Ferreira, Hendrik C.
- Authors: Esenogho, Ebenezer , Mambou, Elie N. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced code , Inversion point , Redundancy
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/403533 , uj:33820 , Citation: Esenogho, E., Mambou, E.N. & Ferreira, H.C. 2019. On the improvement of the Knuth’s redundancy algorithm for balancing codes.
- Description: Abstract: A simple scheme was proposed by Knuth to generate balanced codewords from a random binary information sequence. However, this method presents a redundancy which is twice as that of the full sets of balanced codewords, that is the minimal achievable redundancy. The gap between the Knuth’s algorithm generated redundancy and the minimal one is significantly considerable and can be reduced. This paper attempts to achieve this goal through a method based on information sequence candidates.
- Full Text:
- Authors: Esenogho, Ebenezer , Mambou, Elie N. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Balanced code , Inversion point , Redundancy
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/403533 , uj:33820 , Citation: Esenogho, E., Mambou, E.N. & Ferreira, H.C. 2019. On the improvement of the Knuth’s redundancy algorithm for balancing codes.
- Description: Abstract: A simple scheme was proposed by Knuth to generate balanced codewords from a random binary information sequence. However, this method presents a redundancy which is twice as that of the full sets of balanced codewords, that is the minimal achievable redundancy. The gap between the Knuth’s algorithm generated redundancy and the minimal one is significantly considerable and can be reduced. This paper attempts to achieve this goal through a method based on information sequence candidates.
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Variable- and fixed-length balanced runlength-limited codes based on a Knuth-like balancing method
- Palunˇci´c, Filip, Maharaj, B.T., Ferreira, Hendrik C.
- Authors: Palunˇci´c, Filip , Maharaj, B.T. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Knuth-like balancing method , Balanced codes , Runlength-limited codes
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/403718 , uj:33841 , Citation: Palunˇci´c, F., Maharaj, B.T. & Ferreira, Hendrik C. 2019. Variable- and fixed-length balanced runlength-limited codes based on a Knuth-like balancing method.
- Description: Abstract: A novel Knuth-like balancing method for runlengthlimited words is presented, which forms the basis of new variableand fixed-length balanced runlength-limited codes that improve on the code rate as compared to balanced runlength-limited codes based on Knuth’s original balancing procedure developed by Immink et al. While Knuth’s original balancing procedure, as incorporated by Immink et al., requires the inversion of each bit one at a time, our balancing procedure only inverts the runs as a whole one at a time. The advantage of this approach is that the number of possible inversion points, which needs to be encoded by a redundancy-contributing prefix/suffix, is reduced, thereby allowing a better code rate to be achieved. Furthermore, this balancing method also allows for runlength violating markers which improve, in a number of respects, on the optimal such markers based on Knuth’s original balancing method.
- Full Text:
- Authors: Palunˇci´c, Filip , Maharaj, B.T. , Ferreira, Hendrik C.
- Date: 2019
- Subjects: Knuth-like balancing method , Balanced codes , Runlength-limited codes
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/403718 , uj:33841 , Citation: Palunˇci´c, F., Maharaj, B.T. & Ferreira, Hendrik C. 2019. Variable- and fixed-length balanced runlength-limited codes based on a Knuth-like balancing method.
- Description: Abstract: A novel Knuth-like balancing method for runlengthlimited words is presented, which forms the basis of new variableand fixed-length balanced runlength-limited codes that improve on the code rate as compared to balanced runlength-limited codes based on Knuth’s original balancing procedure developed by Immink et al. While Knuth’s original balancing procedure, as incorporated by Immink et al., requires the inversion of each bit one at a time, our balancing procedure only inverts the runs as a whole one at a time. The advantage of this approach is that the number of possible inversion points, which needs to be encoded by a redundancy-contributing prefix/suffix, is reduced, thereby allowing a better code rate to be achieved. Furthermore, this balancing method also allows for runlength violating markers which improve, in a number of respects, on the optimal such markers based on Knuth’s original balancing method.
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An overview of outdoor visible light communications
- Ndjiongue, A. R., Ferreira, Hendrik C.
- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C.
- Date: 2018
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/273025 , uj:29079 , Citation: Ndjiongue, A.R. & Ferreira, H.C. 2018. An overview of outdoor visible light communications.
- Description: Abstract: In visible light communications (VLC) technology, the outdoor applications are less explored when compared to those indoors. This is due to the fact that: (i) the dual use of light emitting diodes (LEDs) is not always practicable in the outdoor VLC environment; (ii) the level of interference and noise is considerably higher in outdoor VLC; (iii) many other communication technologies are available to be used which, due to their specific characteristics, adapt better to the outdoor environment when compared to VLC technology. Nevertheless, several outdoor VLC applications have been identified. They include and are not limited to building-to-building (B2B), vehicle-to-vehicle (V2V) and road-to-vehicle (R2V) communications. Deploying light fidelity (Li-Fi) using street and park lights is also feasible. Finally, some applications exploit the ability of solar panels to simultaneously harvest the electrical energy and serve as a VLC receiving antenna. The implementation of these communication systems faces lots of challenges. Most of them are related to environmental factors such as fog, rain, sunlight, haze, snow, dust, and atmospheric disturbances. Some challenges are based on parameters such as the geometrical aspect of the light diffusion, which is Lambertian in most cases. These challenges contribute to lower interest in outdoor VLC to date. However, the environment presents several opportunities. In this article, we explore the outdoor VLC environment, review and present some promising applications selected from the literature. Furthermore, we underline likely research opportunities based on the actual state-of-the-art and our outdoor VLC characterisation experiments.
- Full Text:
- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C.
- Date: 2018
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/273025 , uj:29079 , Citation: Ndjiongue, A.R. & Ferreira, H.C. 2018. An overview of outdoor visible light communications.
- Description: Abstract: In visible light communications (VLC) technology, the outdoor applications are less explored when compared to those indoors. This is due to the fact that: (i) the dual use of light emitting diodes (LEDs) is not always practicable in the outdoor VLC environment; (ii) the level of interference and noise is considerably higher in outdoor VLC; (iii) many other communication technologies are available to be used which, due to their specific characteristics, adapt better to the outdoor environment when compared to VLC technology. Nevertheless, several outdoor VLC applications have been identified. They include and are not limited to building-to-building (B2B), vehicle-to-vehicle (V2V) and road-to-vehicle (R2V) communications. Deploying light fidelity (Li-Fi) using street and park lights is also feasible. Finally, some applications exploit the ability of solar panels to simultaneously harvest the electrical energy and serve as a VLC receiving antenna. The implementation of these communication systems faces lots of challenges. Most of them are related to environmental factors such as fog, rain, sunlight, haze, snow, dust, and atmospheric disturbances. Some challenges are based on parameters such as the geometrical aspect of the light diffusion, which is Lambertian in most cases. These challenges contribute to lower interest in outdoor VLC to date. However, the environment presents several opportunities. In this article, we explore the outdoor VLC environment, review and present some promising applications selected from the literature. Furthermore, we underline likely research opportunities based on the actual state-of-the-art and our outdoor VLC characterisation experiments.
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Channel frequency response for a low voltage indoor cable up to 1GHz
- De Beer, A.S, Sheri, A., Ferreira, Hendrik C., Han Vinck, A.J.
- Authors: De Beer, A.S , Sheri, A. , Ferreira, Hendrik C. , Han Vinck, A.J.
- Date: 2018
- Subjects: CFR , Low Voltage Cable , Contactless PLC
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290470 , uj:31534 , Citation: De Beer, A.S. et al. 2018. Channel frequency response for a low voltage indoor cable up to 1GHz.
- Description: Abstract: The Channel Frequency Response (CFR) is essential in the understanding and specification of Power Line Communications (PLC) equipment. In this paper a 10m indoor low voltage Flat Twin and Earth power cable is characterized up to 1GHz. This is higher in frequency than existing PLC specifications. This is done because the effect of frequencies in the upper VHF and lower UHF bands on PLC is largely unknown. Measurements and simulation are used to show that at higher frequencies, the traditional transmission line models of wave propagation on a power line are no longer valid. Classic attenuation models do not predict the correct CFR above typically 250MHz for a 10m cable. This effect is explained in terms of electromagnetic radiation from the cable. After 500MHz it is speculated that the line becomes a waveguide. These transmission modes have important implications for UHF PLC, either directly (connected cable) or when used in contactless mode where the power line is used as antenna.
- Full Text:
- Authors: De Beer, A.S , Sheri, A. , Ferreira, Hendrik C. , Han Vinck, A.J.
- Date: 2018
- Subjects: CFR , Low Voltage Cable , Contactless PLC
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290470 , uj:31534 , Citation: De Beer, A.S. et al. 2018. Channel frequency response for a low voltage indoor cable up to 1GHz.
- Description: Abstract: The Channel Frequency Response (CFR) is essential in the understanding and specification of Power Line Communications (PLC) equipment. In this paper a 10m indoor low voltage Flat Twin and Earth power cable is characterized up to 1GHz. This is higher in frequency than existing PLC specifications. This is done because the effect of frequencies in the upper VHF and lower UHF bands on PLC is largely unknown. Measurements and simulation are used to show that at higher frequencies, the traditional transmission line models of wave propagation on a power line are no longer valid. Classic attenuation models do not predict the correct CFR above typically 250MHz for a 10m cable. This effect is explained in terms of electromagnetic radiation from the cable. After 500MHz it is speculated that the line becomes a waveguide. These transmission modes have important implications for UHF PLC, either directly (connected cable) or when used in contactless mode where the power line is used as antenna.
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Distance-preserving mapping with euclidean distance for 4-ary PAM
- Shongwe, Thokozani, Swart, Theo G., Ferreira, Hendrik C.
- Authors: Shongwe, Thokozani , Swart, Theo G. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: Distance-preserving mappings , Hamming distance , Euclidean distance
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290486 , uj:31536 , Citation: Shongwe, T., Swart, T.G. & Ferreira, H.C. 2018. Distance-preserving mapping with euclidean distance for 4-ary PAM.
- Description: Abstract: In this article we give: (a) a new construction for mapping binary sequences to permutation sequences formed from a 4-PAM constellation, and call the resulting codebooks mappings; (b) a metric for assessing the performance of mappings from our construction; (c) performance results comparing mappings from our construction against the conventional mappings in the literature. The results show that our mappings outperform the conventional mappings. Against conventional soft-decision decoded 4-PAM, our mapping showed 2.4 dB and 3.2 dB improvement over (R = 1=3, K = 4, dfree = 10) and (R = 1=3, K = 3, dfree = 6) convolutional codes, respectively.
- Full Text:
- Authors: Shongwe, Thokozani , Swart, Theo G. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: Distance-preserving mappings , Hamming distance , Euclidean distance
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290486 , uj:31536 , Citation: Shongwe, T., Swart, T.G. & Ferreira, H.C. 2018. Distance-preserving mapping with euclidean distance for 4-ary PAM.
- Description: Abstract: In this article we give: (a) a new construction for mapping binary sequences to permutation sequences formed from a 4-PAM constellation, and call the resulting codebooks mappings; (b) a metric for assessing the performance of mappings from our construction; (c) performance results comparing mappings from our construction against the conventional mappings in the literature. The results show that our mappings outperform the conventional mappings. Against conventional soft-decision decoded 4-PAM, our mapping showed 2.4 dB and 3.2 dB improvement over (R = 1=3, K = 4, dfree = 10) and (R = 1=3, K = 3, dfree = 6) convolutional codes, respectively.
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Influence of cable selection on channel frequency response for low voltage indoor cables
- De Beer, A.S., Sheri, A., Ferreira, Hendrik C.
- Authors: De Beer, A.S. , Sheri, A. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: Low Voltage Cable , PLC , Power Line Communications
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290459 , uj:31533 , Citation: De Beer, A.S., Sheri, A. & Ferreira, H.C. 2018. Influence of cable selection on channel frequency response for low voltage indoor cables.
- Description: Abstract: The Channel Frequency Response (CFR) is an important parameter in the specification of Power Line Communications (PLC) equipment. In this paper, low voltage indoor power cables are investigated and their suitability for PLC operation are determined. This is done in terms of their Channel Frequency Response (CFR). Cable parameters such as inductance, capacitance, resistance, length and termination are investigated up to 100MHz. This work shows cable length and load impedance are the primary factors affecting CFR behavior. Long cables (in the 100’s of meters) and low load impedances - lower that the cable characteristic impedance (few Ω) can dramatically limit the bandwidth of the CFR. Variances in geometry, dielectric and resistance are only secondary effects and do not affect CFR as drastically as length and load impedance.
- Full Text:
- Authors: De Beer, A.S. , Sheri, A. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: Low Voltage Cable , PLC , Power Line Communications
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/290459 , uj:31533 , Citation: De Beer, A.S., Sheri, A. & Ferreira, H.C. 2018. Influence of cable selection on channel frequency response for low voltage indoor cables.
- Description: Abstract: The Channel Frequency Response (CFR) is an important parameter in the specification of Power Line Communications (PLC) equipment. In this paper, low voltage indoor power cables are investigated and their suitability for PLC operation are determined. This is done in terms of their Channel Frequency Response (CFR). Cable parameters such as inductance, capacitance, resistance, length and termination are investigated up to 100MHz. This work shows cable length and load impedance are the primary factors affecting CFR behavior. Long cables (in the 100’s of meters) and low load impedances - lower that the cable characteristic impedance (few Ω) can dramatically limit the bandwidth of the CFR. Variances in geometry, dielectric and resistance are only secondary effects and do not affect CFR as drastically as length and load impedance.
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On the indoor VLC link evaluation based on the racian K-factor
- Ndjiongue, Alain R., Ngatched, Telex M. N., Ferreira, Hendrik C.
- Authors: Ndjiongue, Alain R. , Ngatched, Telex M. N. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: VLC , K-factor , VLC link analysis
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/283726 , uj:30610 , Citation: Ndjiongue, A.R., Ngatched, T.M.N. & Ferreira, H.C. 2018. On the indoor VLC link evaluation based on the racian K-factor.
- Description: Abstract: In visible light communications (VLC) technology, the channel is generally modeled as a multi-path propagation environment. This is due to the presence, on the photo-detector (PD), of specular and non-specular signal components. The Racian K-factor is exploited in such environments to measure the dominance of the line-of-sight (LoS) signal power over that of the non-LoS (NLoS) link. In this paper, K is exploited in the evaluation of the VLC link. Examples of the use of K is underlined in the computation of few link evaluation metrics including the signal-to-noise ratio (SNR), , the channel capacity, C, and the outage probability
- Full Text:
- Authors: Ndjiongue, Alain R. , Ngatched, Telex M. N. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: VLC , K-factor , VLC link analysis
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/283726 , uj:30610 , Citation: Ndjiongue, A.R., Ngatched, T.M.N. & Ferreira, H.C. 2018. On the indoor VLC link evaluation based on the racian K-factor.
- Description: Abstract: In visible light communications (VLC) technology, the channel is generally modeled as a multi-path propagation environment. This is due to the presence, on the photo-detector (PD), of specular and non-specular signal components. The Racian K-factor is exploited in such environments to measure the dominance of the line-of-sight (LoS) signal power over that of the non-LoS (NLoS) link. In this paper, K is exploited in the evaluation of the VLC link. Examples of the use of K is underlined in the computation of few link evaluation metrics including the signal-to-noise ratio (SNR), , the channel capacity, C, and the outage probability
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The effect of coupling circuits on impulsive noise in power line communication
- Samakande, T., Shongwe, T., De Beer,, A.S., Ferreira, Hendrik C.
- Authors: Samakande, T. , Shongwe, T. , De Beer,, A.S. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: PLC , Power Line Communication , Impulse noise
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/291232 , uj:31622 , Citation: Samakande, T. et al. 2018. The effect of coupling circuits on impulsive noise in power line communication.
- Description: Abstract: Most researchers in the Power Line Communications (PLC) field have adopted the practice of using idealized impulse noise models directly at the input of the demodulator, as is widely done in simulations. The effect of the coupling circuit on the impulse noise tend to be ignored. However, coupling circuits produce transients. This paper focuses on investigating the effect of the coupling circuit on the impulse noise. Experimental measurements are used to determine the effect of the coupling circuit. An equivalent circuit of the coupling circuit is developed and further simulations are conducted to gain in-depth knowledge on how the impulse noise is affected by the coupling circuit. A literature survey suggests that this topic has not been studied yet.
- Full Text:
- Authors: Samakande, T. , Shongwe, T. , De Beer,, A.S. , Ferreira, Hendrik C.
- Date: 2018
- Subjects: PLC , Power Line Communication , Impulse noise
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/291232 , uj:31622 , Citation: Samakande, T. et al. 2018. The effect of coupling circuits on impulsive noise in power line communication.
- Description: Abstract: Most researchers in the Power Line Communications (PLC) field have adopted the practice of using idealized impulse noise models directly at the input of the demodulator, as is widely done in simulations. The effect of the coupling circuit on the impulse noise tend to be ignored. However, coupling circuits produce transients. This paper focuses on investigating the effect of the coupling circuit on the impulse noise. Experimental measurements are used to determine the effect of the coupling circuit. An equivalent circuit of the coupling circuit is developed and further simulations are conducted to gain in-depth knowledge on how the impulse noise is affected by the coupling circuit. A literature survey suggests that this topic has not been studied yet.
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A simplistic channel model for cascaded PLC-VLC systems
- Nlom, Stephane M., Ndjiongue, A. R., Ouahada, K., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Nlom, Stephane M. , Ndjiongue, A. R. , Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: Channel model , Cascaded PLC-VLC , PLC and VLC channels
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/237866 , uj:24380 , Citation:
- Description: Abstract: In this a paper, we propose a simplistic channel model for cascaded PLC-VLC system which highlights the noise scenario in such hybrid systems. The model utilises previously proposed channel transfer functions of both PLC and VLC channels and highlights the effects of the LED supply in the system. The noise scenario implemented on the model is based on the observations obtained from a practical measurement of PLC and VLC noise amplitude spectrum (NAS). The PLC-VLC channel is generalised and then simulated based on realistic data. In our results, we highlight the effect of the model’s parameters and noise present in both PLC and VLC channels.
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- Authors: Nlom, Stephane M. , Ndjiongue, A. R. , Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: Channel model , Cascaded PLC-VLC , PLC and VLC channels
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/237866 , uj:24380 , Citation:
- Description: Abstract: In this a paper, we propose a simplistic channel model for cascaded PLC-VLC system which highlights the noise scenario in such hybrid systems. The model utilises previously proposed channel transfer functions of both PLC and VLC channels and highlights the effects of the LED supply in the system. The noise scenario implemented on the model is based on the observations obtained from a practical measurement of PLC and VLC noise amplitude spectrum (NAS). The PLC-VLC channel is generalised and then simulated based on realistic data. In our results, we highlight the effect of the model’s parameters and noise present in both PLC and VLC channels.
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An overview of colour LED & CFL lighting interference on the low voltage PLC network
- Emleh, A., De Beer, A. S., Cheng, L., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Emleh, A. , De Beer, A. S. , Cheng, L. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: CFL , EMC , EN 50065-1
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/247461 , uj:25695 , Citation: Emleh, A. et al. 2017. An overview of colour LED & CFL lighting interference on the low voltage PLC network.
- Description: Abstract: Light sources are being competitive in the current market. Several types of these products have been widely used in the last two decades. They play a major role on the low voltage network as they produce and inject undesired noise onto the transmission lines of the PLC channel. This noise can be of a serious and negative effect when using the power line communications system to control the automatic switching of lamps in residential areas and public places. The main colour low-energy indoor light sources that exist in the market, such as, LEDs and CFLs have been tested for the noise generation on the PLC channel and the results are analyzed and shown in this study. A mathematical analysis of LED bridge rectifier is introduced in this study.
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- Authors: Emleh, A. , De Beer, A. S. , Cheng, L. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: CFL , EMC , EN 50065-1
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/247461 , uj:25695 , Citation: Emleh, A. et al. 2017. An overview of colour LED & CFL lighting interference on the low voltage PLC network.
- Description: Abstract: Light sources are being competitive in the current market. Several types of these products have been widely used in the last two decades. They play a major role on the low voltage network as they produce and inject undesired noise onto the transmission lines of the PLC channel. This noise can be of a serious and negative effect when using the power line communications system to control the automatic switching of lamps in residential areas and public places. The main colour low-energy indoor light sources that exist in the market, such as, LEDs and CFLs have been tested for the noise generation on the PLC channel and the results are analyzed and shown in this study. A mathematical analysis of LED bridge rectifier is introduced in this study.
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Closed-form BER expressions for HSV based MPSK-CSK systems
- Ndjiongue, Alain Richard, Ferreira, Hendrik C., Shongwe, Thokozani
- Authors: Ndjiongue, Alain Richard , Ferreira, Hendrik C. , Shongwe, Thokozani
- Date: 2017
- Subjects: Gaussian channel , RF-VLC systems , Error probability
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/233530 , uj:23844 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Shongwe, T. 2017. Closed-form BER expressions for HSV based MPSK-CSK systems.
- Description: Abstract: The analysis of hybrid phase shift keying-color shift keying (MPSK-CSK) systems under the additive white Gaussian noise model is presented. MPSK-CSK systems are formed by mapping phase shift keying symbols to color shift keying using Hue-Saturation-Value color space. Analytical expressions of bit error rate are given for M = 2, 4, 8 and 16, to validate the simulation results published previously.
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- Authors: Ndjiongue, Alain Richard , Ferreira, Hendrik C. , Shongwe, Thokozani
- Date: 2017
- Subjects: Gaussian channel , RF-VLC systems , Error probability
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/233530 , uj:23844 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Shongwe, T. 2017. Closed-form BER expressions for HSV based MPSK-CSK systems.
- Description: Abstract: The analysis of hybrid phase shift keying-color shift keying (MPSK-CSK) systems under the additive white Gaussian noise model is presented. MPSK-CSK systems are formed by mapping phase shift keying symbols to color shift keying using Hue-Saturation-Value color space. Analytical expressions of bit error rate are given for M = 2, 4, 8 and 16, to validate the simulation results published previously.
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Closed-form SER expression for APSK based on the kite structure
- Ndjiongue, Alain Richard, Ferreira, Hendrik C., Ngatched, Telex M. N.
- Authors: Ndjiongue, Alain Richard , Ferreira, Hendrik C. , Ngatched, Telex M. N.
- Date: 2017
- Subjects: APSK scheme , Kite structure , Closed-form SER
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/244493 , uj:25282 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Ngatched, T.M.N. 2017. Closed-form SER expression for APSK based on the kite structure.
- Description: Abstract: Please refer to full text to view abstract
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- Authors: Ndjiongue, Alain Richard , Ferreira, Hendrik C. , Ngatched, Telex M. N.
- Date: 2017
- Subjects: APSK scheme , Kite structure , Closed-form SER
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/244493 , uj:25282 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Ngatched, T.M.N. 2017. Closed-form SER expression for APSK based on the kite structure.
- Description: Abstract: Please refer to full text to view abstract
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Constellation design for cascaded MPSK-CSK systems
- Ndjiongue, A. R., Ferreira, Hendrik C., Ngatched, Telex M. N.
- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Ngatched, Telex M. N.
- Date: 2017
- Subjects: MPSK-CSK constellation design , Hybrid PLC-VLC systems , MPSK-CSK systems
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/233516 , uj:23843 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Ngatched, T.M.N. 2017. Constellation design for cascaded MPSK-CSK systems.
- Description: Abstract: This paper proposes a constellation design for color shift keying (CSK) based on phase shift keying (PSK) conversion, to be used in cascaded power line communications (PLC) and visible light communications (VLC) systems integration. We optimize the design of MPSK-CSK constellations and analyze the performance of MPSK-CSK systems based on the optimized Euclidean distance calculated on the red-green-blue (RGB) color space.
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- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Ngatched, Telex M. N.
- Date: 2017
- Subjects: MPSK-CSK constellation design , Hybrid PLC-VLC systems , MPSK-CSK systems
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/233516 , uj:23843 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Ngatched, T.M.N. 2017. Constellation design for cascaded MPSK-CSK systems.
- Description: Abstract: This paper proposes a constellation design for color shift keying (CSK) based on phase shift keying (PSK) conversion, to be used in cascaded power line communications (PLC) and visible light communications (VLC) systems integration. We optimize the design of MPSK-CSK constellations and analyze the performance of MPSK-CSK systems based on the optimized Euclidean distance calculated on the red-green-blue (RGB) color space.
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Distributed demand side management with battery storage for smart home energy scheduling
- Longe, Omowunmi Mary, Ouahada, Khmaies, Rimer, Suvendi, Harutyunyan, Ashot N., Ferreira, Hendrik C.
- Authors: Longe, Omowunmi Mary , Ouahada, Khmaies , Rimer, Suvendi , Harutyunyan, Ashot N. , Ferreira, Hendrik C.
- Date: 2017
- Subjects: Demand Side Management (DSM) , Distributed Energy Storage (DES) , Energy Scheduling and Distributed Storage (ESDS) algorithm
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/232094 , uj:23667 , Citation: Longe, O.M. et al. 2017. Distributed demand side management with battery storage for smart home energy scheduling. Sustainability, 8(x):1-4.
- Description: Abstract: The role of Demand Side Management (DSM) with Distributed Energy Storage (DES) has been gaining attention in recent studies due to the impact of the latter on energy management in the smart grid. In this work, an Energy Scheduling and Distributed Storage (ESDS) algorithm is proposed to be installed into the smart meters of Time-of-Use (TOU) pricing consumers possessing in-home energy storage devices. Source of energy supply to the smart home appliances was optimized between the utility grid and the DES device depending on energy tariff and consumer demand satisfaction information. This is to minimize consumer energy expenditure and maximize demand satisfaction simultaneously. The ESDS algorithm was found to offer consumer-friendly and utility-friendly enhancements to the DSM program such as energy, financial, and investment savings, reduced/eliminated consumer dissatisfaction even at peak periods, Peak-to-Average-Ratio (PAR) demand reduction, grid energy sustainability, socio-economic benefits, and other associated benefits such as environmental-friendliness.
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- Authors: Longe, Omowunmi Mary , Ouahada, Khmaies , Rimer, Suvendi , Harutyunyan, Ashot N. , Ferreira, Hendrik C.
- Date: 2017
- Subjects: Demand Side Management (DSM) , Distributed Energy Storage (DES) , Energy Scheduling and Distributed Storage (ESDS) algorithm
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/232094 , uj:23667 , Citation: Longe, O.M. et al. 2017. Distributed demand side management with battery storage for smart home energy scheduling. Sustainability, 8(x):1-4.
- Description: Abstract: The role of Demand Side Management (DSM) with Distributed Energy Storage (DES) has been gaining attention in recent studies due to the impact of the latter on energy management in the smart grid. In this work, an Energy Scheduling and Distributed Storage (ESDS) algorithm is proposed to be installed into the smart meters of Time-of-Use (TOU) pricing consumers possessing in-home energy storage devices. Source of energy supply to the smart home appliances was optimized between the utility grid and the DES device depending on energy tariff and consumer demand satisfaction information. This is to minimize consumer energy expenditure and maximize demand satisfaction simultaneously. The ESDS algorithm was found to offer consumer-friendly and utility-friendly enhancements to the DSM program such as energy, financial, and investment savings, reduced/eliminated consumer dissatisfaction even at peak periods, Peak-to-Average-Ratio (PAR) demand reduction, grid energy sustainability, socio-economic benefits, and other associated benefits such as environmental-friendliness.
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Distributed optimisation algorithm for demand side management in a grid-connected smart microgrid
- Longe, Omowunmi Mary, Ouahada, Khmaies, Rimer, Suvendi, Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Longe, Omowunmi Mary , Ouahada, Khmaies , Rimer, Suvendi , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: Distributed Energy Generation , Distributed Energy Storage , Demand Side Management
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/237901 , uj:24383 , Citation: Longe, O.M. 2017. Distributed optimisation algorithm for demand side management in a grid-connected smart microgrid. Sustainability, 8(x):1-15.
- Description: Abstract: The contributions of Distributed Energy Generation (DEG) and Distributed Energy Storage (DES) for Demand Side Management (DSM) purposes in a smart macrogrid or microgrid cannot be over-emphasised. However, standalone DEG and DES can lead to under-utilisation of energy generation by consumers and financial investments; in grid-connection mode, though, DEG and DES can offer arbitrage opportunities for consumers and utility provider(s). A grid-connected smart microgrid comprising heterogeneous (active and passive) smart consumers, electric vehicles and a large-scale centralised energy storage is considered in this paper. Efficient energy management by each smart entity is carried out by the proposed Microgrid Energy Management Distributed Optimisation Algorithm (MEM-DOA) installed distributively within the network according to consumer type. Each smart consumer optimises its energy consumption and trading for comfort (demand satisfaction) and profit. The proposed model was observed to yield better consumer satisfaction, higher financial savings, and reduced Peak-to-Average-Ratio (PAR) demand on the utility grid. Other associated benefits of the model include reduced investment on peaker plants, grid reliability and environmental benefits. The MEM-DOA also offered participating smart consumers energy and tariff incentives so that passive smart consumers do not benefit more than active smart consumers, as was the case with some previous energy management algorithms.
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- Authors: Longe, Omowunmi Mary , Ouahada, Khmaies , Rimer, Suvendi , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: Distributed Energy Generation , Distributed Energy Storage , Demand Side Management
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/237901 , uj:24383 , Citation: Longe, O.M. 2017. Distributed optimisation algorithm for demand side management in a grid-connected smart microgrid. Sustainability, 8(x):1-15.
- Description: Abstract: The contributions of Distributed Energy Generation (DEG) and Distributed Energy Storage (DES) for Demand Side Management (DSM) purposes in a smart macrogrid or microgrid cannot be over-emphasised. However, standalone DEG and DES can lead to under-utilisation of energy generation by consumers and financial investments; in grid-connection mode, though, DEG and DES can offer arbitrage opportunities for consumers and utility provider(s). A grid-connected smart microgrid comprising heterogeneous (active and passive) smart consumers, electric vehicles and a large-scale centralised energy storage is considered in this paper. Efficient energy management by each smart entity is carried out by the proposed Microgrid Energy Management Distributed Optimisation Algorithm (MEM-DOA) installed distributively within the network according to consumer type. Each smart consumer optimises its energy consumption and trading for comfort (demand satisfaction) and profit. The proposed model was observed to yield better consumer satisfaction, higher financial savings, and reduced Peak-to-Average-Ratio (PAR) demand on the utility grid. Other associated benefits of the model include reduced investment on peaker plants, grid reliability and environmental benefits. The MEM-DOA also offered participating smart consumers energy and tariff incentives so that passive smart consumers do not benefit more than active smart consumers, as was the case with some previous energy management algorithms.
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