• Title/Summary/Keyword: Multi-Rate

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Multi-view Rate Control based on HEVC for 3D Video Services

  • Lim, Woong;Lee, Sooyoun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.8
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    • pp.245-249
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    • 2013
  • In this paper, we propose two rate control algorithms for multi-view extension of HEVC with two rate control algorithms adopted in HEVC and analyze the multi-view rate control performance. The proposed multi-view rate controls are designed on HEVC-based multi-view video coding (MV-HEVC) platform with consideration of high-level syntax, inter-view prediction, etc. not only for the base view but also for the extended views using the rate control algorithms based on URQ (Unified Rate-Quantization) and R-lambda model adopted in HEVC. The proposed multi-view rate controls also contain view-wise target bit allocation for providing the compatibility to the base view. By allocating the target bitrates for each view, the proposed multi-view rate control based on URQ model achieved about 1.83% of average bitrate accuracy and 1.73dB of average PSNR degradation. In addition, about 2.97% of average bitrate accuracy and 0.31dB of average PSNR degradation are achieved with the proposed multi-view rate control based on R-lambda model.

A Rate Separating Multi-Channel Protocol for Improving Channel Diversity and Node Connectivity in IEEE 802.11 Mesh Networks (IEEE 802.11 메쉬 네트워크에서 채널 다양성과 노드 연결성 향상을 위한 레이트 분할 멀티 채널 프로토콜)

  • Kim, Sok-Hyong;Suh, Young-Joo;Kwon, Dong-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.12A
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    • pp.1152-1159
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    • 2010
  • Wireless Mesh Networks (WMNs) provides Internet accesses to users by forming backbone networks via wireless links. A key problem of WMN is network capacity. For this, multi-channel and multi-rate functions of IEEE 802.11 can be utilized. Depending on channel assignments, multi-channel determines node connectivity and channel diversity. Also, in IEEE 802.11 multi-rate networks, the rate anomaly problem occurs, the phenomenon that low-rate links degrades the performance of high-rate links. In this paper, we propose rate separating multi-channel (RSMC) protocols that improves the node connectivity and channel diversity, and mitigates the rate anomaly problem. RSMC increases the channel diversity by forming tree-based WMNs and decreases the rate anomaly by separating different rate links on the tree via channels. In addition, it uses network connectivity (NC) algorithm to increase the node connectivity. Through simulations, we demonstrate that the RSMC shows improved performance than existing multi-channel protocols in terms of aggregate throughput, node connectivity, channel diversity.

Multi-Rate and Multi-BEP Transmission Scheme Using Adaptive Overlapping Pulse-Position Modulator and Power Controller in Optical CDMA Systems

  • Miyazawa Takaya;Sasase Iwao
    • Journal of Communications and Networks
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    • v.7 no.4
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    • pp.462-470
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    • 2005
  • We propose a multi-rate and multi-BEP transmission scheme using adaptive overlapping pulse-position modulator (OPPM) and optical power controller in optical code division multiple access (CDMA) networks. The proposed system achieves the multi-rate and multi-BEP transmission by accommodating users with different values of OPPM parameter and transmitted power in the same network. The proposed scheme has advantages that the system is not required to change the code length and number of weight depending on the required bit rate of a user and the difference of bit rates does not have so much effect on the bit error probabilities (BEPs). Moreover, the difference of transmitted powers does not cause the change of bit rate. We analyze the BEPs of the four multimedia service classes corresponding to the com­binations of high/low-rates and low/high-BEPs and show that the proposed scheme can easily achieve distinct differentiation of the service classes with the simple system configuration.

Effects of Nonlinearity on the Performance of Multi-Code CDMA Communication Systems (Multi-Code CDMA 시스템에서의 비선형 전력 증폭기의 영향분석)

  • 권진만;김상우
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.6A
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    • pp.855-863
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    • 1999
  • Recently a number of multi-rate CDMA systems have been proposed for the third generation mobile communication system. Multi-Code CDMA (MC-CDMA) offers the system construction advantage of being able to use a single-rate receiver. But MC-CDMA suffers from the distortion due to the nonlinearity of the power amplifier. In this paper, we analyze the effect of the nonlinearity on the bit error rate performance of MC-CDMA systems. A polynomial model is used to represent the amplifier amplitude nonlinearities.

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Joint Routing and Channel Assignment in Multi-rate Wireless Mesh Networks

  • Liu, Jiping;Shi, Wenxiao;Wu, Pengxia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.5
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    • pp.2362-2378
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    • 2017
  • To mitigate the performance degradation caused by performance anomaly, a number of channel assignment algorithms have been proposed for multi-rate wireless mesh networks. However, network conditions have not been fully considered for routing process in these algorithms. In this paper, a joint scheme called Multi-rate Dijkstra's Shortest path - Rate Separated (MDSRS) is proposed, combining routing metrics and channel assignment algorithm. In MDSRS, the routing metric are determined through the synthesized deliberations of link costs and rate matches; then the rate separated channel assignment is operated based on the determined routing metric. In this way, the competitions between high and low rate links are avoided, and performance anomaly problem is settled, and the network capacity is efficiently improved. Theoretical analysis and NS-3 simulation results indicate that, the proposed MDSRS can significantly improve the network throughput, and decrease the average end-to-end delay as well as packet loss probability. Performance improvements could be achieved even in the heavy load network conditions.

Adaptive Multi-stage Parallel Interference Cancellation Receiver for a Multi-rate DS-CDMA System (다중전송률 DS-CDMA 시스템을 위한 적응다단병렬간섭제거수신기)

  • 한승희;이재홍
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.89-92
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    • 2001
  • In this paper, adaptive multi-stage parallel interference cancellation (PIC) receiver is considered for a multi-rate DS-CDMA system. In each stage of the adaptive multi-stage PIC receiver, multiple access interference (MAI) estimates are obtained using the sub-bit estimates from the Previous stage and the adaptive weights for the sub-bit estimates. The adaptive weights are obtained by minimizing the mean squared error between the received signal and its estimate through a least mean square (LMS) algorithm. It is shown that the adaptive multi- stage PIC receiver achieves smaller BER than the matched filter receiver, multi-stage PIC receiver, and multi-stage partial PIC receiver for the multi-rate DS-CDMA system in a Rayleigh fading channel.

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A Model-based Rate Separation Algorithm Using Multiple Channels in Multi-Radio Ad Hoc Networks (멀티 라디오 애드혹 네트워크에서의 멀티 채널을 이용한 모델 기반 레이트 분할 알고리즘)

  • Kim, Sok-Hyong;Kim, Dong-Wook;Suh, Young-Joo;Kwon, Dong-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.1A
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    • pp.73-81
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    • 2011
  • IEEE 802.11 PHY and MAC layer provide multiple channels and data rates. To improve the performance of IEEE 802.11 multi-radio ad hoc networks, it is required to utilize available channels and data rates efficiently. However, in IEEE 802.11 multi-rate networks, the rate anomaly (RA) problem occurs that the network performance is severely degraded as low-rate links affect high-rate links. Hence, in this paper, we propose a model-based rate separation (MRS) algorithm that uses multiple channels to separate different data rate links so that the RA problem is mitigated. MRS algorithm utilizes an existing throughput model that estimates the throughput of IEEE 802.11 single-hop networks to separate low-rate links and high-rate links. Through simulations, we demonstrate that the MRS algorithm shows improved network performance compared with existing algorithms in multi-radio ad hoc networks.

Multi-rate Non-recursive Architecture for Cascaded Integrator-Comb Decimation Filters with an Arbitrary Factor (임의의 인수를 갖는 cascaded Integrator-Comb 데시메이션 필터의 Multi-rte Non-recursive 아키텍처)

  • 장영범
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.10B
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    • pp.1785-1792
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    • 2000
  • In this paper multi-rate non-recursive architecture for CIC(Cascaded Integrator-Comb) decimation filters with an arbitrary factor is proposed. The CIC filters are widely used in high speed wireless communication systems since they have multiplier-less and multi-rate low-power structure. Even conventional non-recursive CIC structure is multi-rate this architecture can be structured only in case of M-th power-of-two decimation factor. This paper proposes that muli-rate non-recursive CIC architecture can be structured with an any decimation factor of product form. Power consumption of the proposed architecture is compared with that of the conventional non-recursion architecture.

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Tile Level Rate Control for High Efficiency Video Coding (HEVC) on Multi-core Platform

  • Marzuki, Ismail;Ahn, Yong-Jo;Sim, Donggyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.11a
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    • pp.147-148
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    • 2015
  • This paper proposes a tile level rate control for High Efficiency Video Coding (HEVC). The proposed tile level rate control is designed by considering the multi-core platform of tile in HEVC. The proposed tile level rate control allocates the number of bits for each tile based on the predetermined weight generated from the current picture level rate control. According to the experimental results, the proposed tile level rate control for HEVC on multi-core platform loses negligibly the bitrate accuracy about 0.07% on average over the reference software HM-14.0.

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Multi-Access Points Transmit Power Control Algorithm in Consideration of the Channel Estimation Error and the Multi Rate Service (채널추정 에러와 다중 전송률 서비스를 고려한 다수 개의 엑세스포인트 전송전력제어 알고리즘)

  • Oh, Changyoon
    • Journal of Korea Society of Industrial Information Systems
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    • v.25 no.4
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    • pp.39-47
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    • 2020
  • We propose a multi-access points transmit power control algorithm in consideration of the channel estimation error and the multi-rate service. In the real communication systems, the channel estimation at the receiver side is imperfect due to limited number of pilot symbol usage. Furthermore, the multi-rate service is supported. We theoretically prove the uniqueness and the convergence of the proposed algorithm in multi-rate service environment. The proposed algorithm composes of one inner loop part and one outer loop part. Simulation results show that 1) the inner loop algorithm guarantees convergence of the transmit power level and the multi-rate service, 2) the outer loop algorithm compensates for the channel estimation error.