Ieice Transactions on Fundamentals of Electronics Communications and Computer Sciences, Nov 1, 2009
... Error Probability of MRC in Frequency Selective Nakagami Fading in the Presence of CCI and AC... more ... Error Probability of MRC in Frequency Selective Nakagami Fading in the Presence of CCI and ACI Mohammad Azizur RAHMAN Chin-Sean SUM Ryuhei FUNADA Shigenobu SASAKI Tuncer BAYKAS Junyi WANG Hiroshi HARADA Shuzo KATO Publication IEICE ...
In this paper, we propose a deflection routing scheme for throughput improvement to realize Gbps ... more In this paper, we propose a deflection routing scheme for throughput improvement to realize Gbps millimeter-wave wireless personal area network (mmWave WPAN) system. The upcoming mmWave WPAN system is designed to support transmission of uncompressed high definition TV (HDTV), high speed wireless downloading and docking etc. These data-rate-greedy applications require Gbps-order throughput which can be met by the capability of
2015 IEEE Conference on Standards for Communications and Networking (CSCN), 2015
Optical wireless technology uses light for mobile communications. The idea is to simultaneously c... more Optical wireless technology uses light for mobile communications. The idea is to simultaneously combine the illumination provided by modern high-power light-emitting diodes (LEDs) with high-speed wireless communications. There have been numerous practical demonstrations of this concept, and the technology is now well matured to be deployed in practice. Independent market analysts forecast a high-volume market for mobile communication devices connected to the ubiquitous lighting infrastructure. This paper aims to make optical and wireless industries aware of the requirement for standardization in this area. The authors present the view of the European COST 1101 research network OPTICWISE towards a next-generation optical wireless standard aiming at data rates from 1 Mbit/s to 10 Gbit/s. Besides key technical insights, relevant use cases and main features are described that were recently adopted by the IEEE 802.15.7r1 working group. Moreover, a channel model is introduced to enable assessment of technical proposals.
ABSTRACT In this paper, we present a coexistence protocol design to provide coexistence solution ... more ABSTRACT In this paper, we present a coexistence protocol design to provide coexistence solution among dissimilar or independently operated autonomous decision-making networks in a wireless communication environment over, specifically but not limited to, TV white space (TVWS) frequency bands. The designed coexistence protocol for the information service has three main functionalities: (1) To collect basic information of subscribed TVWS networks; (2) To support generating neighbor lists for the TVWS networks based on the geography information or propagation parameters; (3) To provide the necessary information for TVWS networks to make coexistence decisions. Both theoretical analysis and simulation results shows that the designed coexistence protocol ensures harmonious communication among multiple dissimilar networks and finally achieves coexistence over a particular area with a limited white space channel resource.
2010 Ieee Wireless Communication and Networking Conference, 2010
ABSTRACT Millimeter wave (mmWave) wireless personal area networks (WPANs) could provide multi-Gbp... more ABSTRACT Millimeter wave (mmWave) wireless personal area networks (WPANs) could provide multi-Gbps based data rate for short range communications. However, this ultra high data rate is sensitive to the co-channel interference (CCI). In this paper we use synchronization frame (sync frame) to mitigate possible interference between WPANs. Sync frames could be simply considered as the copies of beacons, which are relayed via the devices associated with the piconet. By using sync frames, the possible CCI could be reduced by increasing per WPAN coverage range, but meanwhile, the spatial reuse capability is also reduced. Therefore, in this work, we are motivated to investigate the optimized beacon/sync frame range at different link distances and its effect to throughput. Simulation results in 60 GHz system for a 2.5 m link indicate that, sync frames can double the guaranteed throughput. For guaranteed throughput of 1.4 Mbps at a 3.5 m link, beacon range can be 35% reduced. Another contribution of the paper is investigating the effect of CCI in 60 GHz systems with spreading 2 and 4. Our results indicate a limited increase in robustness at high CCI situation compared to non spreading cases.
ABSTRACT This paper presents throughput and error performance analysis of the proposed space-time... more ABSTRACT This paper presents throughput and error performance analysis of the proposed space-time resource management (STRM) scheme for a multi-Gbps millimeter-wave system. The proposed STRM allows multiple peer-to-peer communication links to occupy the same time-division-multiple-access (TDMA) time slot, in contrary to the conventional TDMA system that allocates only one time slot to one communication link. In this paper, theoretical analysis is conducted to investigate the achievable throughput in the presence of co-channel interference (CCI) generated by communication links co-sharing the same time slot. Firstly, it is found that the upper bound of the achievable throughput increases linearly with the number of communication links sharing the same time slot. Secondly, by presenting a parameter that manages the allowable CCI in the network, the system throughput can be optimized. The optimum preset allowable CCI values are found to be in the range of -13dB¿CCI¿-11dB. Lastly, it is also found that in a millimeterwave band system, a victim system with transmitter-receiver separation of 1-meter can achieve its targeted bit error rate (BER) provided that the interferer is 6 meters away.
This paper proposes a spatial time-division multiple access (STDMA) throughput enhancement scheme... more This paper proposes a spatial time-division multiple access (STDMA) throughput enhancement scheme for a multi-Gbps millimeter-wave (mmWave) wireless personal area network (WPAN) system. The system design includes in the medium access control (MAC) layer, an interference-monitoring mechanism and a heuristic TDMA time-slot scheduling engine, and in the physical (PHY) layer, a Reed-Solomon (RS) coded phase-shift keying (PSK) system with selective Rake reception over a realistic 60GHz multipath propagation channel. The theoretical analysis of the throughput and error performance is verified by Monte Carlo simulations. Firstly, it is found that the proposed STDMA scheme is capable of improving system throughput as much as 100%. Secondly, the co-channel interference (CCI) in a communication link has to be controlled at/below -15dB in order to achieve the optimum system throughput. Lastly, different tolerable CCI levels to meet respective application requirements are determined.
2010 Ieee 71st Vehicular Technology Conference, May 16, 2010
ABSTRACT In this paper, we propose a spacial time slot scheduling algorithm for relay operation t... more ABSTRACT In this paper, we propose a spacial time slot scheduling algorithm for relay operation to improve the throughput performance of millimeter-wave wireless personal area network (mmWave WPAN) systems which employ directional antenna. The upcoming mmWave WPAN is designed for high definition TV (HDTV) transmission, high speed wireless docking and gaming, etc. Based on the fact that the significant path loss of millimeter-wave environments provides good space isolation, we have proposed a coexistence mechanism by sharing time slots for relay with direct transmission to guarantee throughput for the above data-rate-greedy applications. This paper is an extension that addresses spacial time slot scheduling for relay operation taking the effect of directional antenna into consideration. We model the throughput maximization with scheduling as an integer optimization and solve it by transforming the problem to a max-weight matching problem of a bipartite graph. We propose a scheduling algorithm based on the Kuhn-Munkres algorithm which can be used to solve the max weight matching problem. Simulation results show that there is up to 25% throughput improvement achieved compared with random scheduling method.
High-speed downlink packet access (HSDPA) is an interface of UMTS systems for data communication.... more High-speed downlink packet access (HSDPA) is an interface of UMTS systems for data communication. It combines 16-QAM modulation with low spreading factors to achieve high data rates. Generalized RAKE (G-RAKE) receiver is an advanced receiver, which can be employed in HSDPA to obtain reliable communication. In this work, we investigate iterative methods, which reduce overall complexity requirements of the G-RAKE receiver, without sacrificing its performance. The names of the methods are The Gauss-Seidel (GS), Successive Over-Relaxation (SOR), Conjugate Gradient (CG), and Preconditioned Conjugate Gradient (PCG). Our simulation results show that the PCG method provides the best trade-off between the complexity and required conditions.
2008 Ieee 19th International Symposium on Personal Indoor and Mobile Radio Communications, 2008
This paper investigates the adjacent channel interference (ACI) resistance of a multi-Gbps single... more This paper investigates the adjacent channel interference (ACI) resistance of a multi-Gbps single carrier wireless personal area network (WPAN) operating in the 60GHz millimeter-wave band. The significance of performance degradation due to ACI is investigated corresponding to varying factors such as types of modulation and radio frequency (RF) hardware impairments. The level of modulation scheme is found to change the system resistance against ACI considerably. RF hardware impairments such as power amplifier (PA) non-linearity and phase-locked loop (PLL) phase noise are also major factors affecting ACI generation. The tolerable ACI for WPAN system design is defined as the ACI that causes 0.5dB degradation in required signal to noise ratio (SNR) at bit error rate (BER)=10 −6 . It is found that for a system employing π/2 binary phase shift keying (BPSK) with PA output backoff (OBO)=3dB, ACI=13.5dB causes 0.5dB BER degradation. For systems employing quadrature phase shift keying (QPSK) modulation, the tolerable ACI with PA OBO=3dB and 5dB are observed at 9dB and 15dB, respectively. For modulation schemes with higher levels such as the 16-quadrature amplitude modulation (QAM) system with PA OBO=3dB and 5dB, the tolerable ACI of 1dB and 5dB are observed. Next, the maximum ACI resistance is defined as the tolerable ACI by the system before the BER performance degrades and saturates towards 0.5. The performance of π/2-BPSK system with PA OBO=3dB has maximum resistance against ACI up to 25dB before the BER saturates towards 0.5. Similar performance can be observed in QPSK system, but with PA OBO increased to 5dB. Systems with 16-QAM are found to saturate to BER=0.5 beyond ACI=10dB. Additionally, the presence of PLL phase noise is found to severely compromise the system performance particularly those with higher modulation levels. ACI as low as 0dB is found to cause error floor to 16-QAM systems.
Ieice Transactions on Fundamentals of Electronics Communications and Computer Sciences, Nov 1, 2009
... Error Probability of MRC in Frequency Selective Nakagami Fading in the Presence of CCI and AC... more ... Error Probability of MRC in Frequency Selective Nakagami Fading in the Presence of CCI and ACI Mohammad Azizur RAHMAN Chin-Sean SUM Ryuhei FUNADA Shigenobu SASAKI Tuncer BAYKAS Junyi WANG Hiroshi HARADA Shuzo KATO Publication IEICE ...
In this paper, we propose a deflection routing scheme for throughput improvement to realize Gbps ... more In this paper, we propose a deflection routing scheme for throughput improvement to realize Gbps millimeter-wave wireless personal area network (mmWave WPAN) system. The upcoming mmWave WPAN system is designed to support transmission of uncompressed high definition TV (HDTV), high speed wireless downloading and docking etc. These data-rate-greedy applications require Gbps-order throughput which can be met by the capability of
2015 IEEE Conference on Standards for Communications and Networking (CSCN), 2015
Optical wireless technology uses light for mobile communications. The idea is to simultaneously c... more Optical wireless technology uses light for mobile communications. The idea is to simultaneously combine the illumination provided by modern high-power light-emitting diodes (LEDs) with high-speed wireless communications. There have been numerous practical demonstrations of this concept, and the technology is now well matured to be deployed in practice. Independent market analysts forecast a high-volume market for mobile communication devices connected to the ubiquitous lighting infrastructure. This paper aims to make optical and wireless industries aware of the requirement for standardization in this area. The authors present the view of the European COST 1101 research network OPTICWISE towards a next-generation optical wireless standard aiming at data rates from 1 Mbit/s to 10 Gbit/s. Besides key technical insights, relevant use cases and main features are described that were recently adopted by the IEEE 802.15.7r1 working group. Moreover, a channel model is introduced to enable assessment of technical proposals.
ABSTRACT In this paper, we present a coexistence protocol design to provide coexistence solution ... more ABSTRACT In this paper, we present a coexistence protocol design to provide coexistence solution among dissimilar or independently operated autonomous decision-making networks in a wireless communication environment over, specifically but not limited to, TV white space (TVWS) frequency bands. The designed coexistence protocol for the information service has three main functionalities: (1) To collect basic information of subscribed TVWS networks; (2) To support generating neighbor lists for the TVWS networks based on the geography information or propagation parameters; (3) To provide the necessary information for TVWS networks to make coexistence decisions. Both theoretical analysis and simulation results shows that the designed coexistence protocol ensures harmonious communication among multiple dissimilar networks and finally achieves coexistence over a particular area with a limited white space channel resource.
2010 Ieee Wireless Communication and Networking Conference, 2010
ABSTRACT Millimeter wave (mmWave) wireless personal area networks (WPANs) could provide multi-Gbp... more ABSTRACT Millimeter wave (mmWave) wireless personal area networks (WPANs) could provide multi-Gbps based data rate for short range communications. However, this ultra high data rate is sensitive to the co-channel interference (CCI). In this paper we use synchronization frame (sync frame) to mitigate possible interference between WPANs. Sync frames could be simply considered as the copies of beacons, which are relayed via the devices associated with the piconet. By using sync frames, the possible CCI could be reduced by increasing per WPAN coverage range, but meanwhile, the spatial reuse capability is also reduced. Therefore, in this work, we are motivated to investigate the optimized beacon/sync frame range at different link distances and its effect to throughput. Simulation results in 60 GHz system for a 2.5 m link indicate that, sync frames can double the guaranteed throughput. For guaranteed throughput of 1.4 Mbps at a 3.5 m link, beacon range can be 35% reduced. Another contribution of the paper is investigating the effect of CCI in 60 GHz systems with spreading 2 and 4. Our results indicate a limited increase in robustness at high CCI situation compared to non spreading cases.
ABSTRACT This paper presents throughput and error performance analysis of the proposed space-time... more ABSTRACT This paper presents throughput and error performance analysis of the proposed space-time resource management (STRM) scheme for a multi-Gbps millimeter-wave system. The proposed STRM allows multiple peer-to-peer communication links to occupy the same time-division-multiple-access (TDMA) time slot, in contrary to the conventional TDMA system that allocates only one time slot to one communication link. In this paper, theoretical analysis is conducted to investigate the achievable throughput in the presence of co-channel interference (CCI) generated by communication links co-sharing the same time slot. Firstly, it is found that the upper bound of the achievable throughput increases linearly with the number of communication links sharing the same time slot. Secondly, by presenting a parameter that manages the allowable CCI in the network, the system throughput can be optimized. The optimum preset allowable CCI values are found to be in the range of -13dB¿CCI¿-11dB. Lastly, it is also found that in a millimeterwave band system, a victim system with transmitter-receiver separation of 1-meter can achieve its targeted bit error rate (BER) provided that the interferer is 6 meters away.
This paper proposes a spatial time-division multiple access (STDMA) throughput enhancement scheme... more This paper proposes a spatial time-division multiple access (STDMA) throughput enhancement scheme for a multi-Gbps millimeter-wave (mmWave) wireless personal area network (WPAN) system. The system design includes in the medium access control (MAC) layer, an interference-monitoring mechanism and a heuristic TDMA time-slot scheduling engine, and in the physical (PHY) layer, a Reed-Solomon (RS) coded phase-shift keying (PSK) system with selective Rake reception over a realistic 60GHz multipath propagation channel. The theoretical analysis of the throughput and error performance is verified by Monte Carlo simulations. Firstly, it is found that the proposed STDMA scheme is capable of improving system throughput as much as 100%. Secondly, the co-channel interference (CCI) in a communication link has to be controlled at/below -15dB in order to achieve the optimum system throughput. Lastly, different tolerable CCI levels to meet respective application requirements are determined.
2010 Ieee 71st Vehicular Technology Conference, May 16, 2010
ABSTRACT In this paper, we propose a spacial time slot scheduling algorithm for relay operation t... more ABSTRACT In this paper, we propose a spacial time slot scheduling algorithm for relay operation to improve the throughput performance of millimeter-wave wireless personal area network (mmWave WPAN) systems which employ directional antenna. The upcoming mmWave WPAN is designed for high definition TV (HDTV) transmission, high speed wireless docking and gaming, etc. Based on the fact that the significant path loss of millimeter-wave environments provides good space isolation, we have proposed a coexistence mechanism by sharing time slots for relay with direct transmission to guarantee throughput for the above data-rate-greedy applications. This paper is an extension that addresses spacial time slot scheduling for relay operation taking the effect of directional antenna into consideration. We model the throughput maximization with scheduling as an integer optimization and solve it by transforming the problem to a max-weight matching problem of a bipartite graph. We propose a scheduling algorithm based on the Kuhn-Munkres algorithm which can be used to solve the max weight matching problem. Simulation results show that there is up to 25% throughput improvement achieved compared with random scheduling method.
High-speed downlink packet access (HSDPA) is an interface of UMTS systems for data communication.... more High-speed downlink packet access (HSDPA) is an interface of UMTS systems for data communication. It combines 16-QAM modulation with low spreading factors to achieve high data rates. Generalized RAKE (G-RAKE) receiver is an advanced receiver, which can be employed in HSDPA to obtain reliable communication. In this work, we investigate iterative methods, which reduce overall complexity requirements of the G-RAKE receiver, without sacrificing its performance. The names of the methods are The Gauss-Seidel (GS), Successive Over-Relaxation (SOR), Conjugate Gradient (CG), and Preconditioned Conjugate Gradient (PCG). Our simulation results show that the PCG method provides the best trade-off between the complexity and required conditions.
2008 Ieee 19th International Symposium on Personal Indoor and Mobile Radio Communications, 2008
This paper investigates the adjacent channel interference (ACI) resistance of a multi-Gbps single... more This paper investigates the adjacent channel interference (ACI) resistance of a multi-Gbps single carrier wireless personal area network (WPAN) operating in the 60GHz millimeter-wave band. The significance of performance degradation due to ACI is investigated corresponding to varying factors such as types of modulation and radio frequency (RF) hardware impairments. The level of modulation scheme is found to change the system resistance against ACI considerably. RF hardware impairments such as power amplifier (PA) non-linearity and phase-locked loop (PLL) phase noise are also major factors affecting ACI generation. The tolerable ACI for WPAN system design is defined as the ACI that causes 0.5dB degradation in required signal to noise ratio (SNR) at bit error rate (BER)=10 −6 . It is found that for a system employing π/2 binary phase shift keying (BPSK) with PA output backoff (OBO)=3dB, ACI=13.5dB causes 0.5dB BER degradation. For systems employing quadrature phase shift keying (QPSK) modulation, the tolerable ACI with PA OBO=3dB and 5dB are observed at 9dB and 15dB, respectively. For modulation schemes with higher levels such as the 16-quadrature amplitude modulation (QAM) system with PA OBO=3dB and 5dB, the tolerable ACI of 1dB and 5dB are observed. Next, the maximum ACI resistance is defined as the tolerable ACI by the system before the BER performance degrades and saturates towards 0.5. The performance of π/2-BPSK system with PA OBO=3dB has maximum resistance against ACI up to 25dB before the BER saturates towards 0.5. Similar performance can be observed in QPSK system, but with PA OBO increased to 5dB. Systems with 16-QAM are found to saturate to BER=0.5 beyond ACI=10dB. Additionally, the presence of PLL phase noise is found to severely compromise the system performance particularly those with higher modulation levels. ACI as low as 0dB is found to cause error floor to 16-QAM systems.
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