10 research outputs found
Analysis and optimization of sparse random linear network coding for reliable multicast services
Point-to-multipoint communications are expected to play a pivotal role in next-generation networks. This paper refers to a cellular system transmitting layered multicast services to a multicast group of users. Reliability of communications is ensured via different Random Linear Network Coding (RLNC) techniques. We deal with a fundamental problem: the computational complexity of the RLNC decoder. The higher the number of decoding operations is, the more the user’s computational overhead grows and, consequently, the faster the battery of mobile devices drains. By referring to several sparse RLNC techniques, and without any assumption on the implementation of the RLNC decoder in use, we provide an efficient way to characterise the performance of users targeted by ultra-reliable layered multicast services. The proposed modelling allows to efficiently derive the average number of coded packet transmissions needed to recover one or more service layers. We design a convex resource allocation framework that allows to minimise the complexity of the RLNC decoder by jointly optimising the transmission parameters and the sparsity of the code. The designed optimisation framework also ensures service guarantees to predetermined fractions of users. The performance of the proposed optimisation framework is then investigated in a LTE-A eMBMS network multicasting H.264/SVC video services
Resource Tuned Optimal Random Network Coding for Single Hop Multicast future 5G Networks
Optimal random network coding is reduced complexity in computation of coding coefficients, computation of encoded packets and coefficients are such that minimal transmission bandwidth is enough to transmit coding coefficient to the destinations and decoding process can be carried out as soon as encoded packets are started being received at the destination and decoding process has lower computational complexity. But in traditional random network coding, decoding process is possible only after receiving all encoded packets at receiving nodes. Optimal random network coding also reduces the cost of computation. In this research work, coding coefficient matrix size is determined by the size of layers which defines the number of symbols or packets being involved in coding process. Coding coefficient matrix elements are defined such that it has minimal operations of addition and multiplication during coding and decoding process reducing computational complexity by introducing sparseness in coding coefficients and partial decoding is also possible with the given coding coefficient matrix with systematic sparseness in coding coefficients resulting lower triangular coding coefficients matrix. For the optimal utility of computational resources, depending upon the computational resources unoccupied such as memory available resources budget tuned windowing size is used to define the size of the coefficient matrix
Resource Tuned Optimal Random Network Coding for Single Hop Multicast future 5G Networks
Optimal random network coding is reduced complexity in computation of coding coefficients, computation of encoded packets and coefficients are such that minimal transmission bandwidth is enough to transmit coding coefficient to the destinations and decoding process can be carried out as soon as encoded packets are started being received at the destination and decoding process has lower computational complexity. But in traditional random network coding, decoding process is possible only after receiving all encoded packets at receiving nodes. Optimal random network coding also reduces the cost of computation. In this research work, coding coefficient matrix size is determined by the size of layers which defines the number of symbols or packets being involved in coding process. Coding coefficient matrix elements are defined such that it has minimal operations of addition and multiplication during coding and decoding process reducing computational complexity by introducing sparseness in coding coefficients and partial decoding is also possible with the given coding coefficient matrix with systematic sparseness in coding coefficients resulting lower triangular coding coefficients matrix. For the optimal utility of computational resources, depending upon the computational resources unoccupied such as memory available resources budget tuned windowing size is used to define the size of the coefficient matrix
Random Linear Network Coding for 5G Mobile Video Delivery
An exponential increase in mobile video delivery will continue with the
demand for higher resolution, multi-view and large-scale multicast video
services. Novel fifth generation (5G) 3GPP New Radio (NR) standard will bring a
number of new opportunities for optimizing video delivery across both 5G core
and radio access networks. One of the promising approaches for video quality
adaptation, throughput enhancement and erasure protection is the use of
packet-level random linear network coding (RLNC). In this review paper, we
discuss the integration of RLNC into the 5G NR standard, building upon the
ideas and opportunities identified in 4G LTE. We explicitly identify and
discuss in detail novel 5G NR features that provide support for RLNC-based
video delivery in 5G, thus pointing out to the promising avenues for future
research.Comment: Invited paper for Special Issue "Network and Rateless Coding for
Video Streaming" - MDPI Informatio
Network-coded NOMA with antenna selection for the support of two heterogeneous groups of users
The combination of Non-Orthogonal Multiple Access (NOMA) and Transmit Antenna Selection (TAS) techniques
has recently attracted significant attention due to the low cost,
low complexity and high diversity gains. Meanwhile, Random
Linear Coding (RLC) is considered to be a promising technique
for achieving high reliability and low latency in multicast
communications. In this paper, we consider a downlink system
with a multi-antenna base station and two multicast groups of
single-antenna users, where one group can afford to be served
opportunistically, while the other group consists of comparatively
low power devices with limited processing capabilities that have
strict Quality of Service (QoS) requirements. In order to boost
reliability and satisfy the QoS requirements of the multicast
groups, we propose a cross-layer framework including NOMAbased TAS at the physical layer and RLC at the application
layer. In particular, two low complexity TAS protocols for NOMA
are studied in order to exploit the diversity gain and meet the
QoS requirements. In addition, RLC analysis aims to facilitate
heterogeneous users, such that, sliding window based sparse RLC
is employed for computational restricted users, and conventional
RLC is considered for others. Theoretical expressions that
characterize the performance of the proposed framework are
derived and verified through simulation results
Random Linear Network Coding for 5G Mobile Video Delivery
An exponential increase in mobile video delivery will continue with the demand for higher resolution, multi-view and large-scale multicast video services. Novel fifth generation (5G) 3GPP New Radio (NR) standard will bring a number of new opportunities for optimizing video delivery across both 5G core and radio access networks. One of the promising approaches for video quality adaptation, throughput enhancement and erasure protection is the use of packet-level random linear network coding (RLNC). In this review paper, we discuss the integration of RLNC into the 5G NR standard, building upon the ideas and opportunities identified in 4G LTE. We explicitly identify and discuss in detail novel 5G NR features that provide support for RLNC-based video delivery in 5G, thus pointing out to the promising avenues for future research
Throughput and Delay Optimization of Linear Network Coding in Wireless Broadcast
Linear network coding (LNC) is able to achieve the optimal
throughput of packet-level wireless broadcast, where a sender
wishes to broadcast a set of data packets to a set of receivers
within its transmission range through lossy wireless links. But
the price is a large delay in the recovery of individual data
packets due to network decoding, which may undermine all the
benefits of LNC. However, packet decoding delay minimization and
its relation to throughput maximization have not been well
understood in the network coding literature.
Motivated by this fact, in this thesis we present a comprehensive
study on the joint optimization of throughput and average packet
decoding delay (APDD) for LNC in wireless broadcast. To this end,
we reveal the fundamental performance limits of LNC and study the
performance of three major classes of LNC techniques, including
instantly decodable network coding (IDNC), generation-based LNC,
and throughput-optimal LNC (including random linear network
coding (RLNC)).
Various approaches are taken to accomplish the study, including
1) deriving performance bounds, 2) establishing and modelling
optimization problems, 3) studying the hardness of the
optimization problems and their approximation, 4) developing new
optimal and heuristic techniques that take into account practical
concerns such as receiver feedback frequency and computational
complexity.
Key contributions of this thesis include:
- a necessary and sufficient condition for LNC to achieve the
optimal throughput of wireless broadcast;
- the NP-hardness of APDD minimization;
- lower bounds of the expected APDD of LNC under random packet
erasures;
- the APDD-approximation ratio of throughput-optimal LNC, which
has a value of between 4/3 and 2. In particular, the ratio of
RLNC is exactly 2;
- a novel throughput-optimal, APDD-approximation, and
implementation-friendly LNC technique;
- an optimal implementation of strict IDNC that is robust to
packet erasures;
- a novel generation-based LNC technique that generalizes some of
the existing LNC techniques and enables tunable throughput-delay
tradeoffs