Single Frequency Network Mode Research Articles

Tracking algorithm for passive coherent radar operating in DVB-T2 single frequency network

Target tracking algorithm for aerial targets in DVB-T2 passive coherent radar with transmitter uncertainty is proposed. Transmitter uncertainty raises when a single target is illuminated by the signals from several transmitters operating in a Single Frequency Network mode resulting in several detections from a single target. The algorithm is based on a track fusion method and consists of the target tracking under the assumption that all measurements belong to the single transmitter; association of the tracks from one target caused by different transmitters; fusion of the tracks followed by tracking of the fused tracks. The performance of the proposed algorithm is demonstrated on real data collected during tracking of the airplanes at the airport. It is shown that the algorithm excludes track redundancy and increases track continuity.

Empirical single frequency network threshold for DVB-T2 based on laboratory experiments

DVB-T2 broadcasting with a single frequency network (SFN) allows an efficient management of frequency utilization and extends the coverage area, which will enable more people to view a broadcast. The SFN mode also increases the concentration of the signal in overlap areas. However, some difference of overlap areas in actual use of SFN networks may have some degradation of the received signal due to the effect of the SFN. In this research, we analyze SFN broadcasting in SISO mode. This paper represents the effects of delays on the SFN signal over different delay times within the guard interval (GI) by analyzing the minimum reception threshold. The analysis of received signal power, MER, bBER, LBER, and noise margin are studied using an actual digital television transmitter for the experiment. The results show that the minimum thresholds for a delay time at 0 microseconds will require higher receive signal power than other delay times within the GI. The results of this experiment are useful in designing the SFN network and make it possible to determine the appropriate C/N threshold for the design of the digital terrestrial television network.

Load Balancing Scheme with PTM Mode for Multicast Services Between MBSFN

In long term evolution (LTE) networks, the multicast services can be transmitted by single frequency network (SFN) mode or point-to-multipoint (PTM) mode, and the unicast services are delivered with point-to-point (PTP) mode. To avoid the network congestion in the LTE networks with the multicast and unicast mixed services, a load balancing (LB) scheme with PTM mode is proposed to minimize the demanded radio resources of the maximum load cell. The system model of the demanded radio resources is based on the signal to interference noise ratio (SINR) of multicast services with SFN mode and PTM mode. Then the minimization problem is solved by means of simulated annealing (SA) heuristics. It selects the optimal transmission mode between SFN and PTM for multicast services. Simulation results show that the proposed LB needs less demanded radio resources of the maximum load cell than SFN mode for all the multicast services.

Using LDM to Achieve Seamless Local Service Insertion and Local Program Coverage in SFN Environment

Layered division multiplexing (LDM) is a spectrum efficient non-orthogonal multiplexing technology that has been adopted in the Advanced Television Systems Committee (ATSC) 3.0 Physical Layer Standard as a baseline technology. This paper studies a two-layer LDM with one layer used for providing a global service through a single frequency network (SFN), and the other for providing local coverage/services, such as location targeted advertising or local content insertion. The pilot boosting effect on SNR and co-channel interference is also analyzed. The LDM upper layer can be used to deliver time-division multiplexed mobile-HD and 4k-UHD services. The LDM lower layer with a negative SNR threshold can reliably provide seamless local coverage/service from each SFN transmitter without coverage gaps among adjacent SFN transmitter service areas. No directional receiving antenna is required for the local service reception and receivers simply tune into the stronger signal. In such LDM systems, while the upper layer is operating in a traditional SFN mode, the lower layer operates in a special form of distributed MIMO or gap-filler mode to provide targeted local coverage. For implementing the two-layer system introduced in this paper, only ATSC 3.0 baseline technologies are used, i.e., there is no need to modify the ATSC 3.0 standard. Given the upper and lower layers’ data rate requirements and the SNR thresholds, the lower layer power, with respect to the upper layer (injection level), can be optimized to maximize upper and lower layer performance and coverage. Since the advertisement time of the local service is typically less than 20% of the program time, nonreal time could be used to play-back the local content at five times the transmission bit rate for better (audio/video) service quality.

Resources Allocation Scheme Based on Mode Switch for Multicast Services in MBSFN

The multimedia broadcast and multicast services (MBMS) in 3GPP LTE is characterized by multicast broadcast single frequency network (MBSFN) operation. The multicast services are transmitted by single frequency network (SFN) mode, and the unicast services are delivered with point-to-point (PTP) mode. To avoid the network congestion of the multicast services in MBSFN, a novel resources allocation scheme (RAS) based on mode switch for the multicast services is proposed. The RAS takes advantages of the mode switch between SFN and PTP for the multicast services and minimizes the demanded radio resources of the maximum load cell. The simulation results show that the proposed RAS needs less demanded radio resources of the maximum load cell than SFN mode for all the multicast services.

Min-max load balancing scheme for mixed multicast and unicast services in LTE networks

To avoid the traffic congestion in long term evolution (LTE) networks, a min-max load balancing (LB) scheme is proposed to minimize the demanded radio resources of the maximum loaded cell. For the mixed multicast and unicast services, multicast services are transmitted by single frequency network (SFN) mode and unicast services are delivered with point-to-point (PTP) mode. The min-max LB takes into account point-to-multipoint (PTM) mode for multicast services and selects the proper transmission mode between SFN and PTM for each multicast service to minimize the demanded radio resources of the maximum loaded cell. Based on the solution of this minimization problem, if the maximum loaded cell does not overload, the min-max LB will change PTM mode into SFN mode for multicast services to achieve high quality of service (QoS). Simulation results show that the proposed min-max LB scheme requires less radio resources from the maximum loaded cell than SFN mode for all multicast services.