The Future of the UHF Band Mobile Broadcast Convergence in the UHF Band Philip Kelley 13-07-2016 1 Nokia 2016
MHz Spectrum use in Europe ~2015 The value of the UHF band Licence exempt: DECT, Wi-Fi (2.4 GHz, ) Possible future mobile use: LTE (700 MHz, L- and S- Band, 2.3 GHz,...) Mobile use: GSM (900, 1800 MHz), UMTS (2.1 GHz) LTE (800, 1800, 2600 MHz) Broadcast use: FM, DAB, DVB-T Other services Higher bands around 2 GHz and above deliver capacity in densely populated area Most valuable spectrum e.g. for mobile between ~450 MHz and 1 GHz large area coverage; DVB-T as of today occupies 320 MHz, after 700 MHz repurposing 224 MHz Below ~450 MHz, antennas are too large for handheld use 2 Nokia 2016
Who are Broadcasters? It is appropriate to distinguish between two sorts of broadcasters : Broadcast network operators (BNOs) Media service providers responsible for the choice of the content of the audiovisual service, aka TV channels or Radio channels. In most cases, spectrum is allocated to them. In the following, the focus is on the requirements and business of media service providers. They are challenged by Over The Top (OTT) players and have a compelling need: 1. To offer Replay/Catchup/VoD in addition to their traditional linear service 2. To distribute their contents also to tablets ad smartphones 3 Nokia 2016
Technologies Digital Terrestrial Transmission from High Tower / High Power (HPHT) only address the traditional linear service ADSL, Cable and Fiber transmissions fulfil the first requirement of media service providers, but not the second one LTE Broadcast is the only currently available technology to successfully address the two requirements. It has the terminal ecosystem ready, and it is available in the bands below 1 GHz that make economically sustainable the coverage including rural areas. Furthermore it can operate in hybrid multicast (for linear distribution) and unicast (for replay) modes. 4 Nokia 2016
LTE broadcast builds on existing infrastructure and ecosystem Digital terrestrial television > DVB-T(2), ATSC, ISDB-T & DTMB > Typically not available in smart phones and tablet PCs > High towers require coordination (e.g. Geneva 06) and can use only fractions of the UHF band in any given location > Multiple Frequency Network (MFN) or multiple Single Frequency Networks (SFN) required to cover large areas LTE broadcast > Single global standard > Widest range of devices, latest CODECs, huge number of established BTS sites > Better improved UHF spectrum utilization due to small coordination distances > Single Frequency Network (SFN) for national, regional and local service areas > Incremental cost comparable to DTT, but higher flexibility (adaptive broadcast/unicast split, interactivity) 5 Nokia 2016
Munich embms trial: spectrum configuration LTE DL (and UL) and DTT coexistence K48 K49 K50 K51 K52 K53 K54 K55 K56 K57 K58 K59 3GPP Band 28 Uplink 3GPP Band 28 Downlink DVB-T- Mux (Pro7/ Sat1) Olympic Tower embms trial network Uplink DVB-T- Mux (div priv.) Olympic Tower DVB-T- Mux Hohenpeißenberg DVB-T- Mux (ARD) Olympic Tower DVB-T- Mux (BFS) Olympic Tower embms trial network Downlink V pol. H pol. V pol. H pol. V pol. V pol. H pol. 686 694 702 710 718 726 734 742 750 758 766 774 782 MHz 706 716 duplex distance 55 MHz 761 771 DVB-T transmit power: 100 kw ERP per carrier from TV tower 711 766 DVB-T carriers within the trial LTE uplink spectrum produce in-band interference to the LTE receiver in the base station. Therefore notch filters were deployed. In the trial scenario this is relevant only for combined broadcast/unicast use cases. 6 Nokia 2016
Coexistence and Convergence The Munich trial by the IMB5 consortium demonstrated that DTT HPHT transmission using DVB technology can coexist in vicinity with LTE Broadcast in the same UHF band. This could help addressing mobile terminals. But Replay/VoD requires some form of convergence where uplinks are made available to send individual requests for specific content at a specific time. Broadcasting licenses are not sufficient and Wireless Broadband (WBB) licenses are held by mobile network operators (MNOs). Some form of agreement between holders of broadcasting licenses and WBB licenses is needed for convergence to happen. The business model has not been found yet; meanwhile OTTs gain market share and start to address pay-tv linear service in addition to VoD. Will media service providers take the same road as OTTs and forget about broadcasting licenses and agreements with MNOs at the expense of quality? Or will they contribute to the deployment of a Supplemental Downlink (SDL) network associated with MNOs uplinks? 7 Nokia 2016
LTE in broadcast band 470-694 MHz: Supplemental Downlink (SDL) Supplemental Downlink = additional capacity to exclusive (FDD) band in downlink direction Complements LTE capacity for video streaming and intense audio visual use Easier to coordinate with DTT use than conventional uplink and downlink operation within the band embms as LTE broadcast technology can complement or in the more distant future even replace DVB-T for terrestrial TV distribution in supplemental downlink capacity 470 MHz 694 MHz 700 800 900 Supplemental Downlink Uplink und Downlink Uplink Downlink SDL may provide win-win between DTT and MBB way before 2030 8 Nokia 2016
A Regulatory issue: Are SDL and Replay part of Broadcasting Service? The ITU-R definition of the broadcasting service is: 1.38 broadcasting service: A radiocommunication service in which the transmissions are intended for direct reception by the general public. This service may include sound transmissions, television transmissions or other types of transmission (CS). Provided that the service delivered is intended for direct reception by the general public: Supplemental Downlink (SDL) transmission could belong to the broadcasting service Delivery of data in the downlink channel for a specific user e.g. in the context of Replay could be considered as broadcasting service Administrations clarifying which services can be considered as belonging to the broadcasting service - and which cannot could impact the scene one way or the other. 9 Nokia 2016
Cooperation between broadcast and mobile broadband What could be achieved Distribution of linear audio-visual content to mobile devices Mobile device may become the TV receiver for the large screen Flexible allocation of bandwidth to linear and non-linear content as needed Required capacity can be found in 470-694 MHz Broadcast - Mobile Broadband cooperation can open win-win with more efficient spectrum use 10 Nokia 2016