Multimedia Broadcast Multicast Service Service Research Articles

Cellular Terrestrial Broadcast—Physical Layer Evolution From 3GPP Release 9 to Release 16

We present the latest developments in the physical layer evolution for the transmission of Multimedia Broadcast Multicast Service (MBMS) over fifth generation (5G) cellular networks. We first provide an overview of how the MBMS physical layer has evolved during the initial releases of the Third Generation Partnership Project (3GPP) specifications and provide motivations and insights for key developments that have helped mature MBMS into a competitive broadcasting solution. We provide an overview of dedicated MBMS carriers for Multimedia Broadcast multicast service Single Frequency Network (MBSFN) transmission as well as Orthogonal Frequency Division Multiplexing (OFDM) numerologies with longer cyclic prefixes to support MBSFN transmission over large geographical areas with large distances between cooperating cell sites. Next, we describe the most recent enhancements to the MBMS physical layer, addressing advanced use cases in the recently completed release of the 3GPP specifications (Release 16). First, we describe the physical layer design for enabling MBSFN-based MBMS services for rooftop receivers with inter-site distances between cooperating cell sites as large as 125 km. In this realm, we demonstrate the need for an OFDM numerology with a 300-microsecond cyclic prefix to communicate effectively over channels with very large delay spreads. Next, we explain how support for high mobility up to 250 kmph was added to the standards by using an OFDM numerology that gracefully trades off inter-symbol interference due to large delay spreads and inter-carrier interference due to large doppler spreads to achieve better performance than existing numerologies at high speeds. Finally, we describe the enhancements that were made to the Cell Acquisition Subframe (CAS)—specifically, the introduction of larger aggregation levels for the Physical Downlink Control Channel (PDCCH) and the support of Physical Broadcast Channel (PBCH) repetitions—that significantly increase the coverage for the control and system information associated with MBMS that are carried by these subframes.

Further Enhanced Multimedia Broadcast/Multicast Service in LTE-Advanced Pro

Consumer demand for high definition video is growing, but current Long Term Evolution (LTE) networks lack sufficient capacity to broadcast the typical 10 to 20 TV channels concurrently broadcast in a geographic region. In response to growing demand, the Third Generation Partnership Program initiated a study into TV enhancements for multimedia broadcast/multicast service (MBMS) for LTE. 3GPP's further enhanced MBMS (FeMBMS) enables higher per cell bandwidth for MBMS services, simultaneous reception of both unicast and multicast services from different mobile network operators (MNOs), MBMS-dedicated cells, standalone MBMS, non-subscriber reception of TV services, and larger cell sizes. In addition, shared enhanced MBMS (eMBMS) networks and MBMS transport services enable MNOs to minimize costs from the content providers, while at the same time incentivizing the content providers to exploit LTE for linear TV services. Finally, by utilizing MBMS on demand (MooD) and dynamic MBMS, the resource allocations to the MBMS flows can be dynamically adapted; for example, the users' quality of experience can be further improved beyond that of legacy static MBMS resource allocation. This article describes the enhancements made to LTE eMBMS related to TV services, MooD, and use cases for each of the enhancements. Additionally, MBMS in 5G next-generation radio is also discussed. The scope of this article comprises the terminal, radio access, core architecture, and related services.

An enhanced framework for providing multimedia broadcast/multicast service over heterogeneous networks

Multimedia broadcast multicast service (MBMS) with inherently low requirement for network resources has been proposed as a candidate solution for using such resources in a more efficient manner. On the other hand, the Next Generation Mobile Network (NGMN) combines multiple radio access technologies (RATs) to optimize overall network performance. Handover performance is becoming a vital indicator of the quality experience of mobile user equipment (UE). In contrast to the conventional vertical handover issue, the problem we are facing is how to seamlessly transmit broadcast/multicast sessions among heterogeneous networks. In this paper, we propose a new network entity, media independent broadcast multicast service center (MIBM-SC), to provide seamless handover for broadcast/multicast sessions over heterogeneous networks, by extensions and enhancements of MBMS and media independent information service (MIIS) architectures. Additionally, a network selection scheme and a cell transmission mode selection scheme are proposed for selecting the best target network and best transmission mode. Both schemes are based on a load-aware network capacity estimation algorithm. Simulation results show that the proposed approach has the capability to provide MBMS over heterogeneous networks, with improved handover performance in terms of packet loss rate, throughput, handover delay, cell load, bandwidth usage, and the peak signal-to-noise ratio (PSNR).

Fitness Landscape Analysis for Scalable Multicast RRM Problem in Cellular Network

Abstract This paper aims to solve the Radio Resource Management (RRM) problem for Multimedia Broadcast Multicast Service (MBMS) system in cellular network. We develop a flexible model to perform dynamic radio resource allocation for MBMS service by using metaheuristic approach. We conduct fitness landscape analysis to study the characteristics of the proposed model, which helps us to select appropriate search strategy. Simulation results show that the proposed algorithm provides better performance than existing algorithms.

Research on resource allocation mechanism for MBMS in wireless cellular system

PurposeThe purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and efficient transmission scheme over various types' services. The proposed algorithm is evaluated by simulation results.Design/methodology/approachA big problem for wireless communication is the limited time/frequency resources. Therefore, the most important issue is how to utilize these limited resources to transmit various services over a wireless broadband network, especially for MBMS services. In this paper, resource allocation mechanism in a full unicast system is first analyzed with three classical methods, then improved modulation and coding schemes (MCS) methods are proposed in a full multicast system to improve system throughput and spectral efficiency. Based on the foregoing discussions, research on resource allocation mechanism for mixed multicast and unicast traffic is developed in single‐cell and multi‐cell system (MBSFN, MBMS over single frequency network), respectively. Different transmission proportions between multicast and unicast are analyzed and a multiplexing scenario is also considered.FindingsResource allocation is a hot topic in wireless communication and there are many investigations on it. However, resource allocation for multicast system, especially for mixed multicast and unicast traffic system, is still a problem worthy of further study. Under same transmission condition in a single cell scenario, system throughput in multicast mode is worse than in unicast mode, which is partly because the number of valid date in multicast resource block (RB) is less than the one in unicast in 3GPP LTE/LTE‐A, on the other hand, because that multicast need to select a relative low MCS to satisfy most MBMS users, even the users with a very poor transmission condition. Fortunately, multicast in MBSFN (MBMS over single frequency network) transfer mode can largely improve system performance.Originality/valueImproved MCS selection schemes are proposed for full multicast transmission and three transmission scenarios for mixed multicast and unicast traffic are presented to discuss resource allocation mechanism over various types' services. Simulation results show that system performance of multicast system can be greatly enhanced in MBSFN transmission mode, especially with MIMO technology.

Enhanced radio resource management algorithms for efficient MBMS service provision in UTRAN

As currently specified by 3GPP, Multimedia Broadcast Multicast Service (MBMS) bearer services can be provided within a cell either by Point-to-Point (P-t-P) or Point-to-Multipoint (P-t-M) transmission mode, but not both at the same time. If P-t-P transmission mode is selected for a cell, one Dedicated Channel (DCH) is established for each user within the cell that joined the MBMS service. Otherwise, if P-t-M transmission mode is selected, one Forward Access Channel (FACH) is established covering the whole cell’s area and commonly shared by all the UEs within. In this paper, we highlight the inefficiencies that can be caused with the aforementioned approach and introduce the “Dual Transmission mode cell” in which P-t-P and P-t-M transmissions (i.e. multiple DCHs and FACH) are allowed to coexist within the same cell. Hence, we propose a new radio resource allocation algorithm and solution to address them. Our proposed algorithm considers the instantaneous distribution and movement of the users within the cell and dynamically decides which users will use FACH and which DCH, in such a way that the requested Quality of Service (QoS) is supported with the least amount of transmission power (i.e. capacity) consumption. Moreover, with the “Dual Transmission mode cell”, new types of intra-cell handovers are introduced which we also analyse and propose a new handover algorithm to address them. The performance evaluation carried out showed that our proposed “Dual Transmission mode cell” approach, provides considerable gains, as well as outperforming all other related approaches, such as “UE Counting”, “Power Counting”, “Rate Splitting”, and “FACH with dynamic power setting”, in terms of capacity and link performance efficiency.

An improved mechanism for multiple MBMS sessions assignment in B3G cellular networks

In Universal Mobile Telecommunication System (UMTS), the downlink capacity is limited by the base station transmission power. Therefore, power control plays an important role to minimize the transmitted power shared among unicast and multicast users within a cell. In Multimedia Broadcast/Multicast Service (MBMS), power control targets to the efficient utilization of radio and network resources. However, the expected high demand for such services stresses the need for an efficient scheme, capable of dynamically allocating radio resources to parallel MBMS sessions. This paper proposes a power control mechanism for efficient MBMS session assignment in next generation UMTS networks. The mechanism shares efficiently the available power resources of UMTS base stations to MBMS sessions running in the network. Furthermore, the mechanism is evaluated through several realistic scenarios and the results indicate the ability of the mechanism to utilize efficiently the radio resources and to ensure the service continuity when parallel MBMS services run in the network. Our approach is compared with current 3rd Generation Partnership Project (3GPP) approaches, such as these presented in TS 25.346 and in TR 25.922, in order to highlight the enhancements that it provides.

MBMS Handover control: A new approach for efficient handover in MBMS enabled 3G cellular networks

With the introduction of Multimedia Broadcast Multicast Service (MBMS) system in 3rd Generation (3G) mobile cellular networks , the Radio Network Controller (RNC) for radio resource efficiency can use either Point-to-Point (one Dedicated Channel per User Equipment (UE) in the Cell) or Point-to-Multipoint (one Common Channel shared by all the UEs in the Cell) transmission mode, to distribute the same MBMS content in a Cell. Thus, the mobile users that are on the move and receive an MBMS service may have to deal with dynamic changes of network resources when crossing the Cell’s edge, introducing new types of handovers ( MBMS Handovers ); from Point-to-Point to Point-to-Multipoint transmission mode Cell and vice versa. Executing an MBMS Handover using the existing handover control approach, as described in 3GPP TR 25.922 specifications, results in inefficiencies due to the approach used. In this paper, we highlight these inefficiencies and propose and evaluate a new handover control approach to address them. As illustrated in our performance evaluation, compared to the existing approach, the proposed approach improves the overall system capacity and link performance and avoids any QoS degradation (seamless handover) during an MBMS Handover.