Planning Large Single Frequency Networks for DVB-T2

Abstract

The final coverage and associated performance of a single frequency networks (SFNs) is a joint result of the properties of all transmitters in the SFN. Due to the large number of parameters involved in the process, finding the right configuration is quite complex. The purpose of this paper is to find optimal SFN network configurations for second generation digital terrestrial broadcast system (DVB-T2). Offering more options of system parameters than its predecessor DVB-T, DVB-T2 allows large SFN networks. However, self-interference in SFNs gives rise to restrictions on the maximum intertransmitter distance and the network size. In order to make optimum use of the spectrum, the same frequency can be reused over different geographical areas-beyond the reuse distance to avoid co-channel interference. In this paper, a methodology based on theoretical network models is proposed. A number of network architectures and network reference models are considered here for different reception modes in order to study the effects of key planning factors on the maximum SFN size and minimum reuse distance. The results show that maximum bitrate, network size, and reuse distance are closely related. In addition, it has been found that the guard interval is not the only limiting parameter and that its impact strongly depends on the rest of DVB-T2 mode parameters as well as on the network characteristics (equivalent radiated power, effective height, and intertransmitter distance). Assuming that the carrier to noise ratio requirements are in the vicinity of 20 dB and bitrates over 30 Mb/s, it has been found that the network can be as large as 360 × 360 km (delivering 39.2 Mb/s) or even 720 × 720 km (delivering 37.5 Mb/s). The reuse distance will also have a complex dependency on the DVB-T2 mode and especially the network parameters, ranging from below 100 to 300 km.Index Terms-Maximum size, reuse distance, second generation digital terrestrial broadcast system (DVB-T2), single frequency network (SFN), low-power-low-tower (LPLT), high-power-high-tower (HPHT).

Channel Characteristics for Fixed and Portable DTV Reception in a Single Frequency Network

“…Frequency Network Maurício V. Guerra 1 , Jair L. de A. Filho 1 , Carlos V. Rodriguez Ron 2 , Luiz A. R. da Silva Mello 3 , Pedro V. G. Castellanos 4 parameters are used to characterize the multipath behavior in the SFN network, and an empirical expression was obtained for the relation between them.…”

“…Additional works regarding the evolutionary state-of-art are proposed in [3][4][5][6][7]. In [3], the author presents a design performed for the DVB-T digital terrestrial television network in Greece.…”

“…In [3], the author presents a design performed for the DVB-T digital terrestrial television network in Greece. Optimal SFN network configurations for second generation digital terrestrial broadcast system (DVB-T2) are obtained in [4]. In [5], the authors estimate the reception quality under the SFN environment with the delay spread of two transmitters shorter than the guard interval.…”

Achieving Maximum SFN Size for a DVB-T2 Transmission System

“…In evaluating the network configurations with the purpose to find the ones that best fulfill the specific requirements in the specific service areas, a number of factors such as the existing available infrastructure, the population distribution, terrain databases, buildings and other clutter layers should be taken in consideration (Li et al, 2015). The existing infrastructure of the service areas which is the object of the analyses is covered by two SFNs with the network configuration: 8 MHz bandwidth, 64 QAM, FFT mode 32k, code rate 3/4, GI 1/16 (224µs, 67km), Pilot Pattern 4, rotated mode, extended mode, data rate 31.2 Mbit/s.…”

On the trade-off between spectrum efficiency and transmission cost in traditional and SFN-based broadcast television

“…For SFNs, we assume that w(τ j ) = 1, which is reasonable as long as there exists a guard interval (GI) duration T g such that w(τ j ) ≈ 1 across the entire coverage area [20]. This occurs when the fraction GI over the total OFDM symbol length is small, and ISD is much smaller compared to the distance that a signal can travel during one GI [29]. For example, for T g = 260µs which is equivalent to approximately a 1/16 fraction of a 32K FFT symbol period in a 6MHz channel [20], would meet these requirements for a bandwidth B ≤ 8MHz and a ISD 80km.…”