time slicing is mandatory in DVB-H [18]. A multiplex (called virtual sub-channel in North America) is a group of digital TV channels that are mixed together for broadcast. Next Generation Mobile Communications Ecosystem Existing in DVB-T DVB-T Modulator New with DVB-H MPEG-2 TV Service 8K 4K 2K DVB-H TPS DVB-H IP-Encapsulator Slicing Transmitter Channel Receiver DVB-H DVB-T Demodulator IP-Decapsulator DVB-H TPS Slicing Figure 9.10 DVB-H conceptual view. Reproduced with permission from © 2009 DVB [16] DVB-H service 1 DVB-H service 8 <= 2 Mbit per slice Mbit/s TV programme 3 TV programme 2 Mbit/s Data rate in a DVB-T channel TV programme 1 1 second Figure 9.11 Possible split of the capacity of one DVB-T channel between three TV programs and an additional eight DVB-H services. Reproduced with permission from Reimers C 2006 IEEE [17] IMS, Services and Applications Table 9.4 DVB-H Key attributes Parameters DVB-H Channel Bandwidths (MHz) 5, 6, 7, 8 FFT Sizes 2K, 4K, 8K Modulations QPSK, 16QAM, 64QAM MPE-FEC Yes (optional) Time Slicing Number of active carriers (8MHz) 1705 (2K), 3409 (4K), 6817(8K) Number of data carriers (8 MHz) 1512 (2K), 3024 (4K), 6048 (8K) MPE-FEC: The MPE allows transporting data network protocols on top of MPEG-2 transport streams. A FEC scheme is used in conjunction with MPE to improve the robustness and thus mobility of the signal. The use of MPE-FEC is optional in DVB-H. 4K Mode: DVB-H support QPSK, 16QAM, and 64QAM modulation methods in combination with a convolutional inner code concatenated with an interleaved Reed-Solomon outer code. It allows FFT (Fast Fourier Transform) sizes of 2K, 4K, and 8K. The 4K is the new orthogonal frequency division multiplexing (OFDM) based mode adopted for trading off mobility and single-frequency network (SFN)7 cell size, allowing single-antenna reception in medium SFNs at very high speeds. This gives additional flexibility for the network design [19]. DVB-H is designed to work in VHF-III (170-230 MHz, or a portion of it), UHF-IV/V (470-862 MHz, or a portion 