Waveform clipping in FSK modulated signal to combat impulse noise
- Shongwe, Thokozani, Han Vinck, A. J.
- Authors: Shongwe, Thokozani , Han Vinck, A. J.
- Date: 2018
- Subjects: Frequency Shift Keying , Impulse noise , Clipping
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/284032 , uj:30661 , Citation: Shongwe, T. & Han Vinck, A.J. 2018. Waveform clipping in FSK modulated signal to combat impulse noise.
- Description: Abstract: This article presents results on the pre-processing (clipping/nulling) of impulse noise corrupted signal that is digitally modulated. The novelty of the article is in performing the clipping technique on the waveform of the digitally modulated signal as opposed to working with the constellation of the modulated signal. We present bit error rate performance results of Frequency Shift Keying (FSK) modulation in the presence of impulse noise and AWGN, when clipping is performed. We furthermore, develop closed-form expressions for the bit error rates of FSK modulation in the presence of both AWGN and impulse noise, when clipping of the received signal has been performed.
- Full Text:
- Authors: Shongwe, Thokozani , Han Vinck, A. J.
- Date: 2018
- Subjects: Frequency Shift Keying , Impulse noise , Clipping
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/284032 , uj:30661 , Citation: Shongwe, T. & Han Vinck, A.J. 2018. Waveform clipping in FSK modulated signal to combat impulse noise.
- Description: Abstract: This article presents results on the pre-processing (clipping/nulling) of impulse noise corrupted signal that is digitally modulated. The novelty of the article is in performing the clipping technique on the waveform of the digitally modulated signal as opposed to working with the constellation of the modulated signal. We present bit error rate performance results of Frequency Shift Keying (FSK) modulation in the presence of impulse noise and AWGN, when clipping is performed. We furthermore, develop closed-form expressions for the bit error rates of FSK modulation in the presence of both AWGN and impulse noise, when clipping of the received signal has been performed.
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Low-complexity SOCPBFSK-OOK interface between PLC and VLC channels for low data rate transmission applications
- Ndjiongue, A. R., Ferreira, Hendrik C., Ouahada, K., Han Vinck, A. J.
- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Ouahada, K. , Han Vinck, A. J.
- Date: 2014
- Subjects: Frequency shift keying , Power line communications , Visible light communications
- Type: Book
- Identifier: uj:4747 , http://hdl.handle.net/10210/11733
- Description: This paper studies and proposes a low cost low complexity interface between power line communications (PLC) and visible light communications (VLC) for low data rate transmission applications. The discussion presents the performance of a spread orthogonal continuous phase binary frequency shift keying (SOCPBFSK) receiver combined with an on-off keying (OOK) modulator to relay low data transmission between PLC and VLC channels. The characteristics of the interface are presented. The results of an experimental test using the proposed interface over the European Committee for Electrotechnical Standardization (CENELEC) bands C and D are presented. The eye diagrams of the combined error are presented as well.
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- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Ouahada, K. , Han Vinck, A. J.
- Date: 2014
- Subjects: Frequency shift keying , Power line communications , Visible light communications
- Type: Book
- Identifier: uj:4747 , http://hdl.handle.net/10210/11733
- Description: This paper studies and proposes a low cost low complexity interface between power line communications (PLC) and visible light communications (VLC) for low data rate transmission applications. The discussion presents the performance of a spread orthogonal continuous phase binary frequency shift keying (SOCPBFSK) receiver combined with an on-off keying (OOK) modulator to relay low data transmission between PLC and VLC channels. The characteristics of the interface are presented. The results of an experimental test using the proposed interface over the European Committee for Electrotechnical Standardization (CENELEC) bands C and D are presented. The eye diagrams of the combined error are presented as well.
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PSK to CSK mapping for hybrid systems involving the radio frequency and the visible spectrum
- Ndjiongue, Alain Richard, Shongwe, Thokozani, Ferreira, Hendrik C., Ngatched, Telex, Han Vinck, A. J.
- Authors: Ndjiongue, Alain Richard , Shongwe, Thokozani , Ferreira, Hendrik C. , Ngatched, Telex , Han Vinck, A. J.
- Date: 2017
- Subjects: Visible light communications , Hybrid RF-VLC systems , Complex vectors to colour mapping
- Language: English
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/369467 , http://hdl.handle.net/10210/93807 , uj:20394 , Citation: Ndjiongue, A.R. et al. 2017. PSK to CSK mapping for hybrid systems involving the radio frequency and the visible spectrum.
- Description: Abstract: This paper presents an efficient technique to map phase shift keying (PSK) signalling to colour shift keying (CSK) constellation, to establish a full link in hybrid systems involving the radio frequency (RF) and the visible spectrum. It fits in systems combining (first link) wireless communication technologies such as the wireless fidelity (WiFi) or wired communication technologies such as power line communications (PLC) to visible light communications (VLC) technology (second link). On the first link, PSK technique is used to convey the information, while, on the second link, a technique based on colour variation is deployed. WiFi standards targeted are those that employ PSK as sub-carrier modulation techniques (IEEE 802.11a/11g/11n). The PSK complex constellation observed at the output of the first link is converted into colours using the hue-saturationvalue/ intensity (HSV/I) colour models. The constant lighting required in VLC corresponds with the coordinate I of the HSI and the colour constraint is met by assigning adequate current intensities to the red-green-blue LEDs (RGB-LEDs) used. The design meets the requirements of CSK constellation design outlined in IEEE 802.15.7. The performance of the system is analysed through bit error rate curves obtained by simulations, for binary PSK (BPSK) and quadrature PSK (QPSK), 8PSK and 16PSK constellations. The results show that as the constellation
- Full Text:
- Authors: Ndjiongue, Alain Richard , Shongwe, Thokozani , Ferreira, Hendrik C. , Ngatched, Telex , Han Vinck, A. J.
- Date: 2017
- Subjects: Visible light communications , Hybrid RF-VLC systems , Complex vectors to colour mapping
- Language: English
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/369467 , http://hdl.handle.net/10210/93807 , uj:20394 , Citation: Ndjiongue, A.R. et al. 2017. PSK to CSK mapping for hybrid systems involving the radio frequency and the visible spectrum.
- Description: Abstract: This paper presents an efficient technique to map phase shift keying (PSK) signalling to colour shift keying (CSK) constellation, to establish a full link in hybrid systems involving the radio frequency (RF) and the visible spectrum. It fits in systems combining (first link) wireless communication technologies such as the wireless fidelity (WiFi) or wired communication technologies such as power line communications (PLC) to visible light communications (VLC) technology (second link). On the first link, PSK technique is used to convey the information, while, on the second link, a technique based on colour variation is deployed. WiFi standards targeted are those that employ PSK as sub-carrier modulation techniques (IEEE 802.11a/11g/11n). The PSK complex constellation observed at the output of the first link is converted into colours using the hue-saturationvalue/ intensity (HSV/I) colour models. The constant lighting required in VLC corresponds with the coordinate I of the HSI and the colour constraint is met by assigning adequate current intensities to the red-green-blue LEDs (RGB-LEDs) used. The design meets the requirements of CSK constellation design outlined in IEEE 802.15.7. The performance of the system is analysed through bit error rate curves obtained by simulations, for binary PSK (BPSK) and quadrature PSK (QPSK), 8PSK and 16PSK constellations. The results show that as the constellation
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Combined spectral shaping codes and OFDM modulation for narrowband interference channels
- Ouahada, K., Ferreira, Hendrik C., Han Vinck, A. J., Snyders, A. J., Swart, Theo G.
- Authors: Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J. , Snyders, A. J. , Swart, Theo G.
- Date: 2008
- Subjects: Distance-preserving mappings , Spectral nulls codes , Spectral shaping codes , OFDM modulation , Narrowband interference
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/21215 , uj:16126 , Citation: Ouahada, K. et al. 2008. Combined spectral shaping codes and OFDM modulation for narrowband interference channels. SAIEE Africa Research Journal, 99(1):11-17.
- Description: Abstract: Distance Preserving Mappings is a relatively new technique finding its way to a wide use in the coding field. New codes mapping convolutional code outputs onto spectral nulls codewords have the purpose of generating a code with a certain spectrum specification and error correction capabilities, which can be exploited by the Viterbi decoder. Combining this class of new codes with an Orthogonal Frequency Division Multiplexing modulation scheme is actually a tool to reduce Electromagnetic Compatibility Interference in selected subbands or to cancel the narrowband interference potentially caused by, amongst others, high frequency radio transmissions. Taking into consideration the fact that a narrowband noise source is almost similar to a modulated orthogonal frequency division multiplexing carrier, and also the periodicity of the nulls in our spectrum, we are able to cancel the narrowband signal and its sideband interferences without using traditional techniques of cancellation, which is based on filtering. Shaping our spectrum at the transmitter is a technique, which can be exploited at the receiver to suppress any narrowband signal interference, which is regarded as noise. We will present in this paper the technique of cancellation and the coding gain that can be obtained when comparing to the uncoded data.
- Full Text:
- Authors: Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J. , Snyders, A. J. , Swart, Theo G.
- Date: 2008
- Subjects: Distance-preserving mappings , Spectral nulls codes , Spectral shaping codes , OFDM modulation , Narrowband interference
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/21215 , uj:16126 , Citation: Ouahada, K. et al. 2008. Combined spectral shaping codes and OFDM modulation for narrowband interference channels. SAIEE Africa Research Journal, 99(1):11-17.
- Description: Abstract: Distance Preserving Mappings is a relatively new technique finding its way to a wide use in the coding field. New codes mapping convolutional code outputs onto spectral nulls codewords have the purpose of generating a code with a certain spectrum specification and error correction capabilities, which can be exploited by the Viterbi decoder. Combining this class of new codes with an Orthogonal Frequency Division Multiplexing modulation scheme is actually a tool to reduce Electromagnetic Compatibility Interference in selected subbands or to cancel the narrowband interference potentially caused by, amongst others, high frequency radio transmissions. Taking into consideration the fact that a narrowband noise source is almost similar to a modulated orthogonal frequency division multiplexing carrier, and also the periodicity of the nulls in our spectrum, we are able to cancel the narrowband signal and its sideband interferences without using traditional techniques of cancellation, which is based on filtering. Shaping our spectrum at the transmitter is a technique, which can be exploited at the receiver to suppress any narrowband signal interference, which is regarded as noise. We will present in this paper the technique of cancellation and the coding gain that can be obtained when comparing to the uncoded data.
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On the binary input Gaussian wiretap channel with/without output quantization
- Qi, Chao, Chen, Yanling, Han Vinck, A. J.
- Authors: Qi, Chao , Chen, Yanling , Han Vinck, A. J.
- Date: 2017
- Subjects: Binary input Gaussian wiretap channel , Information theoretic security , Secrecy capacity
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/231903 , uj:23637 , Citation: Qi, C., Chen, Y. & Han Vinck, A.J. 2017. On the binary input Gaussian wiretap channel with/without output quantization. Entropy, 19,59. DOI:10.3390/e19020059.
- Description: Abstract: In this paper, we investigate the effect of output quantization on the secrecy capacity of the binary-input Gaussian wiretap channel. As a result, a closed-form expression with infinite summation terms of the secrecy capacity of the binary-input Gaussian wiretap channel is derived for the case when both the legitimate receiver and the eavesdropper have unquantized outputs. In particular, computable tight upper and lower bounds on the secrecy capacity are obtained. Theoretically, we prove that when the legitimate receiver has unquantized outputs while the eavesdropper has binary quantized outputs, the secrecy capacity is larger than that when both the legitimate receiver and the eavesdropper have unquantized outputs or both have binary quantized outputs. Further, numerical results show that in the low signal-to-noise ratio (SNR) (of the main channel) region, the secrecy capacity of the binary input Gaussian wiretap channel when both the legitimate receiver and the eavesdropper have unquantized outputs is larger than the capacity when both the legitimate receiver and the eavesdropper have binary quantized outputs; as the SNR increases, the secrecy capacity when both the legitimate receiver and the eavesdropper have binary quantized outputs tends to overtake.
- Full Text:
- Authors: Qi, Chao , Chen, Yanling , Han Vinck, A. J.
- Date: 2017
- Subjects: Binary input Gaussian wiretap channel , Information theoretic security , Secrecy capacity
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/231903 , uj:23637 , Citation: Qi, C., Chen, Y. & Han Vinck, A.J. 2017. On the binary input Gaussian wiretap channel with/without output quantization. Entropy, 19,59. DOI:10.3390/e19020059.
- Description: Abstract: In this paper, we investigate the effect of output quantization on the secrecy capacity of the binary-input Gaussian wiretap channel. As a result, a closed-form expression with infinite summation terms of the secrecy capacity of the binary-input Gaussian wiretap channel is derived for the case when both the legitimate receiver and the eavesdropper have unquantized outputs. In particular, computable tight upper and lower bounds on the secrecy capacity are obtained. Theoretically, we prove that when the legitimate receiver has unquantized outputs while the eavesdropper has binary quantized outputs, the secrecy capacity is larger than that when both the legitimate receiver and the eavesdropper have unquantized outputs or both have binary quantized outputs. Further, numerical results show that in the low signal-to-noise ratio (SNR) (of the main channel) region, the secrecy capacity of the binary input Gaussian wiretap channel when both the legitimate receiver and the eavesdropper have unquantized outputs is larger than the capacity when both the legitimate receiver and the eavesdropper have binary quantized outputs; as the SNR increases, the secrecy capacity when both the legitimate receiver and the eavesdropper have binary quantized outputs tends to overtake.
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Cascaded PLC-VLC channel using OFDM and CSK techniques
- Ndjiongue. A. R., Shongwe, Thokozani, Ferreira, Hendrik C., Ngatched, T. M. Nkouatchah, Han Vinck, A. J.
- Authors: Ndjiongue. A. R. , Shongwe, Thokozani , Ferreira, Hendrik C. , Ngatched, T. M. Nkouatchah , Han Vinck, A. J.
- Date: 2016
- Subjects: PLC-OFDM , Hybrid systems , Cascaded channels
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/92561 , uj:20242 , Citation: Ndjiongue, A.R. et al. 2016. Cascaded PLC-VLC channel using OFDM and CSK techniques.
- Description: Abstract: This paper puts in Cascade the power line communications (PLC) channel and the visible light communications (VLC) channel, in order to use the PLC channel as backbone for the VLC channel. This combination is suitable for applications in which hybrid PLC-VLC systems are needed. We investigate the behaviour of the cascaded channels for a full link transmission. Quadrature phase shift keying combined with orthogonal frequency division multiplexing (QPSK-OFDM) is used over the PLC channel and color shift keying (CSK) is deployed over the VLC channel to convey the information. Cascaded channel variances are analyzed. Complete simulated bit error rate (BER) is analyzed and presented for multiple scenarii that could occur in the two channels.
- Full Text:
- Authors: Ndjiongue. A. R. , Shongwe, Thokozani , Ferreira, Hendrik C. , Ngatched, T. M. Nkouatchah , Han Vinck, A. J.
- Date: 2016
- Subjects: PLC-OFDM , Hybrid systems , Cascaded channels
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/92561 , uj:20242 , Citation: Ndjiongue, A.R. et al. 2016. Cascaded PLC-VLC channel using OFDM and CSK techniques.
- Description: Abstract: This paper puts in Cascade the power line communications (PLC) channel and the visible light communications (VLC) channel, in order to use the PLC channel as backbone for the VLC channel. This combination is suitable for applications in which hybrid PLC-VLC systems are needed. We investigate the behaviour of the cascaded channels for a full link transmission. Quadrature phase shift keying combined with orthogonal frequency division multiplexing (QPSK-OFDM) is used over the PLC channel and color shift keying (CSK) is deployed over the VLC channel to convey the information. Cascaded channel variances are analyzed. Complete simulated bit error rate (BER) is analyzed and presented for multiple scenarii that could occur in the two channels.
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Impedance analysis of a power line distribution network using short-time Fourier transform
- Sanya, Timothy O., Shongwe, Thokozani, Han Vinck, A. J., Ferreira, Hendrik C.
- Authors: Sanya, Timothy O. , Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2017
- Subjects: DFT , STFT , Impedance
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/248176 , uj:25791 , Citation: Sanya, T.O. et al. 2017. Impedance analysis of a power line distribution network using short-time Fourier transform.
- Description: Abstract: The impedance of a low voltage distribution network is analyzed and presented. Data collected from field measurement which was done over one week is used in this analysis. Basically, a chirp is injected into the electric grid, and the voltage and current signals (corrupted by various noises, including the 50 Hz mains signal) are time-sampled and stored for processing. The voltage and current are processed to obtain the impedance of the electric grid. Simulations are performed to establish the efficacy of the method of analysis used to obtain the impedance. The sliding window method of the Discrete Fourier Transform (DFT) is used in analyzing these impedance values. An eventual channel model describing the network is also presented.
- Full Text:
- Authors: Sanya, Timothy O. , Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2017
- Subjects: DFT , STFT , Impedance
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/248176 , uj:25791 , Citation: Sanya, T.O. et al. 2017. Impedance analysis of a power line distribution network using short-time Fourier transform.
- Description: Abstract: The impedance of a low voltage distribution network is analyzed and presented. Data collected from field measurement which was done over one week is used in this analysis. Basically, a chirp is injected into the electric grid, and the voltage and current signals (corrupted by various noises, including the 50 Hz mains signal) are time-sampled and stored for processing. The voltage and current are processed to obtain the impedance of the electric grid. Simulations are performed to establish the efficacy of the method of analysis used to obtain the impedance. The sliding window method of the Discrete Fourier Transform (DFT) is used in analyzing these impedance values. An eventual channel model describing the network is also presented.
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A study on impulse noise and its models
- Shongwe, Thokozani, Han Vinck, A. J., Ferreira, Hendrik C.
- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2015
- Subjects: Impulse noise models , Multi-carrier modulation , Single-carrier modulation
- Language: English
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/380056 , http://hdl.handle.net/10210/73970 , uj:18479 , Citation: Shongwe, T., Han Vinck, A.J. & Ferreira, H.C. 2015. A study on impulse noise and its models.
- Description: Abstract: Please refer to full text to view abstract
- Full Text:
- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2015
- Subjects: Impulse noise models , Multi-carrier modulation , Single-carrier modulation
- Language: English
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/380056 , http://hdl.handle.net/10210/73970 , uj:18479 , Citation: Shongwe, T., Han Vinck, A.J. & Ferreira, H.C. 2015. A study on impulse noise and its models.
- Description: Abstract: Please refer to full text to view abstract
- Full Text:
Analysis of the devolo’s 500 kHz G3-PLC access technology based on smart grid field trials
- Papilaya, V. N., Han Vinck, A. J., Ouahada, K., Mengi, A., Weinand, M., Koch, M., devolo, AG
- Authors: Papilaya, V. N. , Han Vinck, A. J. , Ouahada, K. , Mengi, A. , Weinand, M. , Koch, M. , devolo, AG
- Date: 2014
- Subjects: Smart grid field trials , G3-PLC access technology
- Type: Article
- Identifier: uj:4799 , http://hdl.handle.net/10210/12053
- Description: In the smart grid, the G3-PLC solution is in direct competition with other IP-based communications technologies such as GPRS or DSL. In this paper, we present the devolo’s 500 kHz G3-PLC access technology and it’s analysis based on smart grid field trials in Germany. The focus of the analysis in this paper is concentrated on the following parameters: The influencing factor of near and far transmission throughput, the influence of a repeater on the throughput, and the influence of different UDP packet size on the throughput.
- Full Text: false
- Authors: Papilaya, V. N. , Han Vinck, A. J. , Ouahada, K. , Mengi, A. , Weinand, M. , Koch, M. , devolo, AG
- Date: 2014
- Subjects: Smart grid field trials , G3-PLC access technology
- Type: Article
- Identifier: uj:4799 , http://hdl.handle.net/10210/12053
- Description: In the smart grid, the G3-PLC solution is in direct competition with other IP-based communications technologies such as GPRS or DSL. In this paper, we present the devolo’s 500 kHz G3-PLC access technology and it’s analysis based on smart grid field trials in Germany. The focus of the analysis in this paper is concentrated on the following parameters: The influencing factor of near and far transmission throughput, the influence of a repeater on the throughput, and the influence of different UDP packet size on the throughput.
- Full Text: false
Simulation results for permutation trellis codes using M-ary FSK
- Swart, Theo G., De Beer, I., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Swart, Theo G. , De Beer, I. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2005
- Subjects: Channel coding , Convolutional codes , Interference suppression
- Language: English
- Type: Conference proceedings
- Identifier: http://ujcontent.uj.ac.za8080/10210/368327 , http://hdl.handle.net/10210/18512 , uj:16008 , Citation: Swart, T.G. et al. 2005. Simulation results for permutation trellis codes using M-ary FSK. Proceedings of the IEEE International Symposium on Power Line Communications and its Applications, 6-8 April, 2005, Vancouver, Canada.
- Description: Abstract: It has previously been shown that using the combination of permutation codes and M-ary frequency shift keying has special properties and error correcting capabilities that are suitable for the noise types encountered in power line communications. Furthermore, the permutation codes are used to map onto the outputs of a binary convolutional code to form permutation trellis codes. We investigate and compare the performance of different permutation trellis codes when used with M-FSK for power line communications.
- Full Text:
- Authors: Swart, Theo G. , De Beer, I. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2005
- Subjects: Channel coding , Convolutional codes , Interference suppression
- Language: English
- Type: Conference proceedings
- Identifier: http://ujcontent.uj.ac.za8080/10210/368327 , http://hdl.handle.net/10210/18512 , uj:16008 , Citation: Swart, T.G. et al. 2005. Simulation results for permutation trellis codes using M-ary FSK. Proceedings of the IEEE International Symposium on Power Line Communications and its Applications, 6-8 April, 2005, Vancouver, Canada.
- Description: Abstract: It has previously been shown that using the combination of permutation codes and M-ary frequency shift keying has special properties and error correcting capabilities that are suitable for the noise types encountered in power line communications. Furthermore, the permutation codes are used to map onto the outputs of a binary convolutional code to form permutation trellis codes. We investigate and compare the performance of different permutation trellis codes when used with M-FSK for power line communications.
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A preliminary investigation of the UHF properties of LV cable for WiFi over power line communications
- Jordaan, Sean, Janse van Rensburg, Petrus A., De Beer, Arnold S., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Jordaan, Sean , Janse van Rensburg, Petrus A. , De Beer, Arnold S. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2015-03-29
- Subjects: Power line communications , Wireless protocol , Wireless communication systems
- Type: Article
- Identifier: uj:5244 , http://hdl.handle.net/10210/14844
- Description: In pursuit of a wireless (contactless) power line communications (W-PLC) system for low voltage (LV) power distribution networks, a commonly utilized bundled low voltage electrical cable called Cabtyre, was energized with a range of frequencies up to 3 GHz. The intention was to characterize the cable from a radio frequency radiation perspective for the utilization of standard low voltage distribution cables as antennas in ultra high frequency (UHF) PLC systems. The range of test frequencies extends 550 MHz beyond the present IEEE 802.11g protocol which has a centre frequency of 2.45 GHz and a 80 MHz total bandwidth. The applied tests therefore allow adequately for the maximum bandwidth required with 40 MHz modulation on either side of the 2.45 GHz centre frequency.
- Full Text:
- Authors: Jordaan, Sean , Janse van Rensburg, Petrus A. , De Beer, Arnold S. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2015-03-29
- Subjects: Power line communications , Wireless protocol , Wireless communication systems
- Type: Article
- Identifier: uj:5244 , http://hdl.handle.net/10210/14844
- Description: In pursuit of a wireless (contactless) power line communications (W-PLC) system for low voltage (LV) power distribution networks, a commonly utilized bundled low voltage electrical cable called Cabtyre, was energized with a range of frequencies up to 3 GHz. The intention was to characterize the cable from a radio frequency radiation perspective for the utilization of standard low voltage distribution cables as antennas in ultra high frequency (UHF) PLC systems. The range of test frequencies extends 550 MHz beyond the present IEEE 802.11g protocol which has a centre frequency of 2.45 GHz and a 80 MHz total bandwidth. The applied tests therefore allow adequately for the maximum bandwidth required with 40 MHz modulation on either side of the 2.45 GHz centre frequency.
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Interleaving and nulling to combat narrow-band interference in PLC standard technologies PLC G3 and PRIME
- Shongwe, Thokozani, Han Vinck, A. J.
- Authors: Shongwe, Thokozani , Han Vinck, A. J.
- Date: 2013
- Subjects: Power line communications , Narrow-band interference
- Type: Article
- Identifier: uj:4748 , ISSN 978-1-4673-6015-9 , http://hdl.handle.net/10210/11734
- Description: Three functional blocks of the PRIME and PLC G3 technologies (encoder/decoder, interleaver, and modulator) are studied in detail, for a PLC channel with narrow-band interference (NBI). The study reveals that these three blocks can be used together effectively so as to improve the performance of the overall system in the presence of NBI. We therefore present effective methods for combating NBI in PRIME and PLC G3, based on these three functional blocks.
- Full Text:
- Authors: Shongwe, Thokozani , Han Vinck, A. J.
- Date: 2013
- Subjects: Power line communications , Narrow-band interference
- Type: Article
- Identifier: uj:4748 , ISSN 978-1-4673-6015-9 , http://hdl.handle.net/10210/11734
- Description: Three functional blocks of the PRIME and PLC G3 technologies (encoder/decoder, interleaver, and modulator) are studied in detail, for a PLC channel with narrow-band interference (NBI). The study reveals that these three blocks can be used together effectively so as to improve the performance of the overall system in the presence of NBI. We therefore present effective methods for combating NBI in PRIME and PLC G3, based on these three functional blocks.
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Noise generated by modern lamps and the influence on the smart-grid communication network
- Emleh, A., De Beer, A. S., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Emleh, A. , De Beer, A. S. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2016
- Subjects: Metal halide lamp , Electronic ballast , Electromagnetic ballast
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/123877 , uj:20846 , Citation: Emleh, A. et al. 2016. Noise generated by modern lamps and the influence on the smart-grid communication network.
- Description: Abstract: The metal halide lamp is a high energy electric lamp that produces visible light by an electric arc tube and it is a type of high-intensity discharge (HID) that contains a fused quartz and mixture of gases. These lamps inject noise into the smart-grid power line communications (PLC) network. This can have a strong and negative effect when using the PLC system to control the automatic switching of lamps in public places. In this paper we investigate the effects when the metal halide lamps with electronic or electromagnetic ballasts are seen as noise sources on the smart-grid power line network. It is shown that in the CENELEC band: (3 kHz – 150 kHz) the interference level from metal halide lamps is significantly below the allowed maximum PLC signal levels. In the band 150 kHz – 30 MHz however, PLC signals compete with Electromagnetic Compatibility (EMC) levels. The operational methods of the electronic and electromagnetic ballasts when connected to the metal halide lamps are explained.
- Full Text:
- Authors: Emleh, A. , De Beer, A. S. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2016
- Subjects: Metal halide lamp , Electronic ballast , Electromagnetic ballast
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/123877 , uj:20846 , Citation: Emleh, A. et al. 2016. Noise generated by modern lamps and the influence on the smart-grid communication network.
- Description: Abstract: The metal halide lamp is a high energy electric lamp that produces visible light by an electric arc tube and it is a type of high-intensity discharge (HID) that contains a fused quartz and mixture of gases. These lamps inject noise into the smart-grid power line communications (PLC) network. This can have a strong and negative effect when using the PLC system to control the automatic switching of lamps in public places. In this paper we investigate the effects when the metal halide lamps with electronic or electromagnetic ballasts are seen as noise sources on the smart-grid power line network. It is shown that in the CENELEC band: (3 kHz – 150 kHz) the interference level from metal halide lamps is significantly below the allowed maximum PLC signal levels. In the band 150 kHz – 30 MHz however, PLC signals compete with Electromagnetic Compatibility (EMC) levels. The operational methods of the electronic and electromagnetic ballasts when connected to the metal halide lamps are explained.
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Detecting the zero-crossing message to achieve low bit transmission over H-bridge inverter
- Ndjiongue, A. R., Han Vinck, A. J., Ouahada, K., Ferreira, Hendrik C., Snyders, A. J.
- Authors: Ndjiongue, A. R. , Han Vinck, A. J. , Ouahada, K. , Ferreira, Hendrik C. , Snyders, A. J.
- Date: 2014
- Subjects: Power line communications , Pulse width modulation
- Type: Article
- Identifier: uj:4753 , http://hdl.handle.net/10210/11739
- Description: Home automation and smart grid development is motivated by many advantageous situations that include the demands on renewable energy and the advantages provided by power line communications technology (PLC). The integration of solar energy into conventional grid implies the control of different modules included in the system. Remote control seems to be the control mode by excellence, in which communication is the main point to focus on. The pulse width modulation (PWM) scheme used to control the inverter is also used to modulate the zero-crossing point of the output sine wave of the inverter, to transfer data. The zero-crossing modulation technique is proposed and basic elements to construct the model are proposed. Simulated constellations of the received signal are presented.
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- Authors: Ndjiongue, A. R. , Han Vinck, A. J. , Ouahada, K. , Ferreira, Hendrik C. , Snyders, A. J.
- Date: 2014
- Subjects: Power line communications , Pulse width modulation
- Type: Article
- Identifier: uj:4753 , http://hdl.handle.net/10210/11739
- Description: Home automation and smart grid development is motivated by many advantageous situations that include the demands on renewable energy and the advantages provided by power line communications technology (PLC). The integration of solar energy into conventional grid implies the control of different modules included in the system. Remote control seems to be the control mode by excellence, in which communication is the main point to focus on. The pulse width modulation (PWM) scheme used to control the inverter is also used to modulate the zero-crossing point of the output sine wave of the inverter, to transfer data. The zero-crossing modulation technique is proposed and basic elements to construct the model are proposed. Simulated constellations of the received signal are presented.
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Reducing the probability of sync-word false acquisition with Reed-Solomon codes
- Shongwe, Thokozani, Han Vinck, A. J., Ferreira, Hendrik C.
- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2013
- Subjects: Reed-Solomon codes , Sync-words , Sync-word based synchronization
- Type: Article
- Identifier: uj:4754 , ISSN 1555-5798 , http://hdl.handle.net/10210/11740
- Description: In our previous work we introduced a method for avoiding/excluding some symbols in Reed-Solomon (RS) codes, called symbol avoidance. In this paper, we apply the symbol avoidance method in sync-word based synchronization of RS encoded data. With the symbol avoidance method we reduce the probability of the RS encoded data being mistaken for the sync-word used to delimit the start/end of the data. The symbols in the RS code are avoided according to the sync-word used, such that the sync-word has very low probability of being found in the RS codewords, where it was not inserted. Therefore, for different sync-words, different symbols need to be avoided in the RS code. The goal here is to reduce the probability of false acquisition of the sync-word in the RS encoded framed data.
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- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2013
- Subjects: Reed-Solomon codes , Sync-words , Sync-word based synchronization
- Type: Article
- Identifier: uj:4754 , ISSN 1555-5798 , http://hdl.handle.net/10210/11740
- Description: In our previous work we introduced a method for avoiding/excluding some symbols in Reed-Solomon (RS) codes, called symbol avoidance. In this paper, we apply the symbol avoidance method in sync-word based synchronization of RS encoded data. With the symbol avoidance method we reduce the probability of the RS encoded data being mistaken for the sync-word used to delimit the start/end of the data. The symbols in the RS code are avoided according to the sync-word used, such that the sync-word has very low probability of being found in the RS codewords, where it was not inserted. Therefore, for different sync-words, different symbols need to be avoided in the RS code. The goal here is to reduce the probability of false acquisition of the sync-word in the RS encoded framed data.
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Segmental analysis of the transmission in CSK systems based on the Euclidean distance
- Ndjiongue, A. R., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2015
- Subjects: CSK
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/69625 , uj:17891 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Han Vinck, A.J. 2015. Segmental analysis of the transmission in CSK systems based on the Euclidean distance.
- Description: Abstract: This article presents a segmental analysis of the transmission in colour shift keying (CSK). The Euclidean distance is fractionally studied to find the distance limits between the observed and the expected points. Practical segmental characterisation of the CSK receiver is presented to verify the Voronoi segmentation over the CSK channel and confirm crosstalk and correlation between the red, green and blue channels based on the threshold selection.
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- Authors: Ndjiongue, A. R. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2015
- Subjects: CSK
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/69625 , uj:17891 , Citation: Ndjiongue, A.R., Ferreira, H.C. & Han Vinck, A.J. 2015. Segmental analysis of the transmission in CSK systems based on the Euclidean distance.
- Description: Abstract: This article presents a segmental analysis of the transmission in colour shift keying (CSK). The Euclidean distance is fractionally studied to find the distance limits between the observed and the expected points. Practical segmental characterisation of the CSK receiver is presented to verify the Voronoi segmentation over the CSK channel and confirm crosstalk and correlation between the red, green and blue channels based on the threshold selection.
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On impulse noise and its models
- Shongwe, Thokozani, Han Vinck, A. J., Ferreira, Hendrik C.
- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2014
- Subjects: Impulse noise models , Multi-carrier modulation , Single-carrier modulation , Bernoulli-Gaussian model , Middleton Class A model
- Type: Article
- Identifier: uj:4728 , ISSN 978-1-4799-4961-8 , http://hdl.handle.net/10210/11553
- Description: This article gives a discussion on impulse noise, its models and how it affects communications systems. We discuss the different impulse noise models in the literature, looking at their similarities and differences in communications systems. The impulse noise models discussed are memoryless (Middleton Class A and Bernoulli-Gaussian), and with memory (Markov- Middleton and Markov-Gaussian). We then go further to give performance comparisons in terms of bit error rates for some of the variants of impulse noise models. We also compare the bit error rate performance of single-carrier (SC) and multicarrier (MC) communications systems operating under impulse noise. It can be seen that MC is not always better than SC under impulse noise. Lastly, the known impulse noise mitigation schemes (clipping/nulling using thresholds, iterative based and error control coding methods) are discussed.
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- Authors: Shongwe, Thokozani , Han Vinck, A. J. , Ferreira, Hendrik C.
- Date: 2014
- Subjects: Impulse noise models , Multi-carrier modulation , Single-carrier modulation , Bernoulli-Gaussian model , Middleton Class A model
- Type: Article
- Identifier: uj:4728 , ISSN 978-1-4799-4961-8 , http://hdl.handle.net/10210/11553
- Description: This article gives a discussion on impulse noise, its models and how it affects communications systems. We discuss the different impulse noise models in the literature, looking at their similarities and differences in communications systems. The impulse noise models discussed are memoryless (Middleton Class A and Bernoulli-Gaussian), and with memory (Markov- Middleton and Markov-Gaussian). We then go further to give performance comparisons in terms of bit error rates for some of the variants of impulse noise models. We also compare the bit error rate performance of single-carrier (SC) and multicarrier (MC) communications systems operating under impulse noise. It can be seen that MC is not always better than SC under impulse noise. Lastly, the known impulse noise mitigation schemes (clipping/nulling using thresholds, iterative based and error control coding methods) are discussed.
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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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Cancellation and error correction for narrowband interference with spectral nulls codes and OFDM modulation
- Ouahada, K., Ferreira, Hendrik C., Han Vinck, A. J., Snyders, A. J., Swart, Theo G.
- Authors: Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J. , Snyders, A. J. , Swart, Theo G.
- Date: 2007
- Subjects: Error-correcting codes (Information theory) , Spectral nulls codes
- Language: English
- Identifier: http://hdl.handle.net/10210/18135 , uj:15964 , Citation: Ouahada, K. et al. 2007. Cancellation and error correction for narrowband interference with spectral nulls codes and OFDM modulation. Proceedings of IEEE Africon, 26-28 September, 2007, Windhoek, Namibia.
- Description: Conference proceedings
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- Authors: Ouahada, K. , Ferreira, Hendrik C. , Han Vinck, A. J. , Snyders, A. J. , Swart, Theo G.
- Date: 2007
- Subjects: Error-correcting codes (Information theory) , Spectral nulls codes
- Language: English
- Identifier: http://hdl.handle.net/10210/18135 , uj:15964 , Citation: Ouahada, K. et al. 2007. Cancellation and error correction for narrowband interference with spectral nulls codes and OFDM modulation. Proceedings of IEEE Africon, 26-28 September, 2007, Windhoek, Namibia.
- Description: Conference proceedings
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Influence of LED tubes on the throughput of an indoor broadband PLC channel
- De Beer, A. S., Emleh, A., Ferreira, Hendrik C., Han Vinck, A. J.
- Authors: De Beer, A. S. , Emleh, A. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: EMC , Interference , LED Tubes
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/247465 , uj:25694 , Citation: De Beer, A.S. et al. 2017. Influence of LED tubes on the throughput of an indoor broadband PLC channel.
- Description: Abstract: This paper shows how Light Emitting Diode (LED) Tubes negatively influence the data rate throughput of an indoor broadband Power Line Communications (PLC) channel. This negative influence on the data rate is due to noise being generated by the lamps. Differential Mode measurements were done with two PLC modems communicating and then introducing LED lamps that add noise to the channel. Drops in data throughput rates were measured and compared to a clean (no noise) channel. A significant decrease (up to 50%) in throughput was observed which can have important implications for applications of PLC in the presence of LED Tubes.
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- Authors: De Beer, A. S. , Emleh, A. , Ferreira, Hendrik C. , Han Vinck, A. J.
- Date: 2017
- Subjects: EMC , Interference , LED Tubes
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/247465 , uj:25694 , Citation: De Beer, A.S. et al. 2017. Influence of LED tubes on the throughput of an indoor broadband PLC channel.
- Description: Abstract: This paper shows how Light Emitting Diode (LED) Tubes negatively influence the data rate throughput of an indoor broadband Power Line Communications (PLC) channel. This negative influence on the data rate is due to noise being generated by the lamps. Differential Mode measurements were done with two PLC modems communicating and then introducing LED lamps that add noise to the channel. Drops in data throughput rates were measured and compared to a clean (no noise) channel. A significant decrease (up to 50%) in throughput was observed which can have important implications for applications of PLC in the presence of LED Tubes.
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