Low Power Low Tower SFN networks Interference Analysis

Transcription

1 Low Power Low Tower SFN networks Interference Analysis 1/44

2 TABLE OF CONTENT Part A - Overview... 3 A.1 - Background... 3 A.2 - Objectives... 4 A.3 - Planning assumptions... 5 A Simulation parameters... 5 A Time model for signal contribution / interference... 6 A Propagation model used for the simulations... 7 Part B - Overall coverage simulations... 7 B.1 - Geographic area and base stations... 7 B.2 - Network configurations analyzed B.3 - Configuration B.4 - Configuration B Simulation results B Analysis of interfered areas in SFN 4 ploygon B.5 - Configuration B.6 - Configuration B.7 - Configuration Part C - Local optimization in difficult areas...35 C.1 - Configuration C.2 - Configuration Part D - Overall analysis of the solution studied /44

3 Part A - Overview This portion will provide an overview of the deployment topology proposed, as well as the coverage objectives within dense areas or rural areas. The overview will also set the performance targets and underlying assumptions on the technology deployed. A.1 - Background The MHz has been historically used in Europe for terrestrial broadcast network, delivering public and private broadcast through fixed rooftop reception. Advances in technology and evolution of consumer habits have triggered discussions about the future use of the MHz. In particular, there is a trend towards mobile consumption for audiovisual content (including audiovisual media services) creating the necessity to consider how broadcasting and mobile services could complement each other in the delivery of audiovisual (both linear and non-linear) content to mobile terminals. The topic was discussed in the High Level Group on the future use of the UHF band led by Pascal Lamy and the Plum Consulting/Farncombe study on broadcast-broadband convergence, both initiatives from the European Commission. From the CEPT side, the ECC Report 224 on Long Term Vision for the UHF broadcasting band described, in particular, a number of scenarios corresponding to convergence of broadcast services on the mobile platform. All reports and study groups acknowledged the potential of a converged platform, designed as a Low Power Low Tower network operating in Supplemental DL mode as a nationwide Single Frequency Network (SFN). While technical feasibility of such an approach was recognized, reports stressed that further studies were required in order to address precisely the coverage achieved by such networks at the border between two SFNs. The study below aims at providing a full assessment of the coverage properties of downlink LPLT networks for the delivery of broadcast content, especially at the border of two SFNs. The technical proposal is to reuse existing base stations operated by mobile operators to deliver an LTE Broadcast service in the MHz band. Reusing existing sites provides numerous benefits, in particular in order to reduce the cost of deployment of such a network. The service should deliver 2 bps/hz to mobile devices and fixed rooftop antennas alike, in order to significantly increase the capacity of the mobile platform. The LTE Broadcast service considered corresponds to an evolution of the current LTE embms standard, in particular in order to support longer cyclic prefixes (200 µsec). One of the benefits of adopting LTE as a standard for broadcasting is to leverage the advanced signal processing capabilities of LTE terminals. LTE embms only requires 16dB of SINR to deliver 2bps/Hz in a very challenging mobile environment. Fixed rooftop reception is ensured with much lower SINR requirements. LTE receivers also support features - such as interference cancellation - which improve performance in challenging SNIR environment. Mobile networks deliver high geographical coverage over either 900 and/or 800 MHz networks. Reusing such sites to deliver LTE broadcast at 2bps/Hz is quite straightforward in terms of pure coverage properties. Challenges arise at the border of two such Single Frequency Networks, for example at the border between two countries. In such area, the signal strength of the desired signal is similar, or even sometimes slightly lower, than the signal from the neighboring (and in this case interfering) network. Fixed rooftop antenna typically offer 16dB of back-to-front ratio, meaning that in the case where both signal deliver similar signal strength, adequate pointing of the fixed rooftop antenna ensures that the desired signal is received with around 16dB signal to interference ratio. 3/44

4 Given that the SINR required for fixed rooftop reception is significantly lower than 16dB and that LTE receiver implement interference cancellation algorithm, the theoretical analysis indicates that fixed rooftop reception should be possible, even at the border between two SFNs. A.2 - Objectives Early studies submitted to ECC TG6 by several DVB-T research groups questioned the feasibility of fixed rooftop reception at the border between two SFNs. In particular, the BBC proposed a study based on some small regional SFNs in England and the selection of base stations from the 900 MHz network of one UK MNO. The study assumed specific transmission site characteristics and that the LTE receiver would behave in a similar manner than a DVB-T receiver, in particular with regards to signals received outside of cyclic prefix length and interfering signal from adjacent SFNs. Under such assumption, the coverage was demonstrated to be quite consistent inside one SFN, but challenging at SFNs borders. In the following sections, the BBC study is extended in order to: -Reuse the BBC site selection, -adopt realistic LTE receiver characteristics, -determine the coverage of such a network under various receiving modes, -determine whether the coverage of such an SFN can be optimized to match the border of administrative broadcasting regions. The study objectives are then the following: - Select existing sites from UK mobile operators and build different networks (up to 7), each SFN having its own coverage area. - Provide SINR maps on the geographical area that will: - Take into account an extended cyclic prefix of 200µs. - Take into account different receiving antenna configurations (standard fixed rooftop antenna, advanced fixed rooftop antenna with excellent front to back ratio, mobile terminal antenna). - Take into account SFN self-interference, and interference from neighboring SFNs. - Perform a network optimization where required (Power, downtilt, antenna base stations, orientation of the receiving antennas, identification of solutions in areas with strong difficulties). The presentation of results would be, based on maps of the BBC, to show how the non-reception zones will be modified with: - Optimization of the transmission network. - Use of receiving antennas with better performance in areas with strong interference. - In extreme cases, use of two receiving antennas for joint reception at the boundary of two SFNs. - Conversely, identify intra SFN areas where the mobile reception would be possible. 4/44

5 A.3 - Planning assumptions A Simulation parameters The following receiving thresholds have been used for the three different antenna configurations. Fixed Fixed advanced Mobile Receiver Noise (dbm) Min SNIR required (db) Transmitting Gain (dbi) Receiving Gain (dbi) Receiving Threshold (dbm) Receiving Threshold (dbµv/m) The following parameters have been also considered for the three different antenna configurations. Fixed Antenna Advanced Fixed Antenna Mobile Antenna Frequency (MHz) RF Allocated Bandwidth (MHz) Target SINR 2bps/Hz (db) Rx Ant Gain (dbi) Antenna diagram Noise level at Antenna connector taking into account Thermal Noise Floor (-104.3dB) Rx Noise Figure (6dB), desense and implementation/cable loss (3dB) ITU-R BT.419 See diagram below Building Penetration 0 0 Omni Rural: 0 Suburban: 10 Light urban (8m): 10 Urban (15m): 10 Dense urban(30m): 10 Rejection of interference from other SFNs (db) At least 3dB 3dB 3dB 10dB X-polar 10dB 5/44

6 Advanced fixed receiving antenna pattern: The receiving antenna height is set to 10m above ground level for fixed reception and 1.5m above ground level for mobile reception. A Time model for signal contribution / interference If we assume that: - Delta TOA is the propagation delay between the reference SFN signal and another signal received; - SR=Signal level received from the reference signal; - S=Useful contribution to the reference signal; - I=Interference level; we have: for Delta TOA<0µs, I=SR, S=0; for 0us<=Delta TOA<=200µs, S=SR, I=0; for 200us<Delta TOA 400µs, S= SR x [1-0.8x((Delta TOA -200)/200)], I = SR x 0.8x((Delta TOA - 200)/200); for Delta TOA>=400us, I=SR, S=0. 6/44

7 A Propagation model used for the simulations Free space losses computed according to ITU-R P.525. Diffraction model: Deygout 94. Subpath attenuation model (to take account of obstacles in the first Fresnel zone): Standard. Part B - Overall coverage simulations The section will present the geographic area studied, including the SFN contours, and the assumptions on the positioning of Base Stations. 7 different network configurations of the respective SFN coverages will then be conducted. Each simulation will determine the coverage zone for each SFN and also determine the overall coverage map, i.e. identify zones with either no reception, reception of 1 SFN, reception of 2 SFNs or reception of 3 SFNs. B.1 - Geographic area and base stations The area of the study in England, in the North of London. The cartographic dataset is made of two main layers: - a digital terrain model of 50m resolution containing the elevation of the ground on each point. 7/44

8 - a 50m resolution clutter layer describing the ground occupancy with 11 classes 8/44

9 Code 0 Rural 0m AGL Code 1 Suburban 6m AGL Code 2 Urban 8m 8m AGL Code 3 Urban 10m 10m AGL Code 4 Urban 32m 12m AGL Code 5 Forest 10m AGL Code 6 Water 0m AGL Code 8 Wood 6m AGL Code 9 Building 10m AGL Code 10 Rail 0m AGL Code 11 Road 0m AGL 9/44

10 7 SFNs have been considered with the following contours: 10/44

11 A selection of O2 (mobile operator) sites has been made to build each SFN. The location of each one with associated information is listed in the table below. Callsign Code Longitude Latitude Altitude Antenna height AGL 4DMS 4DMS (m) (m) SFN ID 261 SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SP W N SFN 1 11/44

12 2189 SP W N SFN TF W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SP W N SFN SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN TF W N SFN SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SP W N SFN SK W N SFN 1 12/44

13 34926 SP W N SFN SP W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN SK W N SFN TF W N SFN SK W N SFN SK W N SFN TF W N SFN TF W N SFN TF W N SFN TF W N SFN TF W N SFN SK W N SFN TF W N SFN TF W N SFN TF W N SFN TF E N SFN TF W N SFN TF E N SFN TL E N SFN TL E N SFN TL E N SFN TM E N SFN TM E N SFN TL E N SFN TG E N SFN TM E N SFN TM E N SFN 3 13/44

14 279 TM E N SFN TL E N SFN TM E N SFN TL E N SFN TG E N SFN TL E N SFN TQ E N SFN TL E N SFN TL E N SFN TF E N SFN TL E N SFN TL E N SFN TL E N SFN TM E N SFN TL E N SFN TQ E N SFN TG E N SFN TG E N SFN TL E N SFN TL E N SFN TM E N SFN TL E N SFN TG E N SFN TM E N SFN TM E N SFN TL E N SFN TL E N SFN TM E N SFN TM E N SFN TG E N SFN TF E N SFN TM E N SFN TM E N SFN TF E N SFN TF E N SFN TF E N SFN TM E N SFN TG E N SFN TL E N SFN TF E N SFN TG E N SFN TF E N SFN TG E N SFN 3 14/44

15 3465 TM E N SFN TL E N SFN TM E N SFN TM E N SFN TQ E N SFN TF E N SFN TL E N SFN TL E N SFN TL E N SFN TM E N SFN TM E N SFN TF E N SFN TF E N SFN TF E N SFN TF E N SFN TG E N SFN TL E N SFN TM E N SFN TF E N SFN TM E N SFN TM E N SFN TL E N SFN TG E N SFN TM E N SFN TM E N SFN TL E N SFN TM E N SFN TM E N SFN TL E N SFN TG E N SFN TG E N SFN TL E N SFN TL E N SFN TM E N SFN TL E N SFN TL E N SFN TF E N SFN TM E N SFN TM E N SFN TL E N SFN TM E N SFN TM E N SFN 3 15/44

16 TM E N SFN 3 TF E N SFN 3 TQ E N SFN 3 TG E N SFN 3 TG E N SFN 3 TG E N SFN 3 TM E N SFN 3 TM E N SFN 3 TM E N SFN 3 TM E N SFN 3 TM E N SFN 3 TF E N SFN 3 TL E N SFN 3 TM E N SFN 3 TQ E N SFN 3 TG E N SFN 3 TF E N SFN 3 TF E N SFN 3 TM E N SFN 3 TL E N SFN 3 TL E N SFN 3 TL E N SFN 3 TF E N SFN 3 16/44

17 54116 TM E N SFN TL E N SFN TM E N SFN TL E N SFN TG E N SFN TL E N SFN TL E N SFN 3 O NEW 0E N SFN TL W N SFN SP W N SFN TL W N SFN SP W N SFN SP W N SFN TL W N SFN TL W N SFN TL W N SFN SP W N SFN SP W N SFN TL E+00 52N SFN SP W N SFN TF W N SFN TL E N SFN SP W N SFN TL W N SFN TL W N SFN TL W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN TF E N SFN TL W N SFN TL E N SFN TL W N SFN TL W N SFN TF W N SFN 4 17/44

18 2932 TL W N SFN TL E N SFN TL W N SFN TL E N SFN TL W N SFN TL W N SFN TF W N SFN TL W N SFN TL E N SFN SP W N SFN SP W N SFN SP W N SFN TL E N SFN TL W N SFN TL E N SFN TL E N SFN SP W N SFN SP W N SFN TL E N SFN SP W N SFN TL W N SFN TL E N SFN SP W N SFN TL W N SFN TL W N SFN TL W N SFN TF W N SFN TL W N SFN SP W N SFN SP W N SFN SP W N SFN TL W N SFN TL E N SFN 4 18/44

19 19585 TL W N SFN SP W N SFN SP W N SFN TL W N SFN SP W N SFN TL W N SFN SP W N SFN SP W N SFN TL W N SFN TL W N SFN SP W N SFN SP W N SFN TL W N SFN TL W N SFN TL E N SFN TL W N SFN TL W N SFN SP W N SFN TL W N SFN 4 O NEW 0E N SFN 4 O NEW 0E N SFN 4 O NEW 0E N SFN 4 Add TL E N SFN 4 99 SP W N SFN SP W N SFN 5 19/44

20 181 SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SU W N SFN SP W N SFN SP W N SFN SP W N SFN SU W N SFN SP W N SFN SU W N SFN SP W N SFN SP W N SFN SU W N SFN SU W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN 5 52 TL W N SFN 6 54 TL W N SFN 6 74 TL W N SFN TL W N SFN TL W N SFN 6 20/44

21 396 TL W N SFN TL E N SFN TL E N SFN SU W N SFN SU W N SFN TL W N SFN SU W N SFN TQ E N SFN TL E+00 51N SFN TL W N SFN TL W N SFN TL W N SFN TL W N SFN TL W N SFN TL E N SFN SU W N SFN TL W N SFN TQ E N SFN TQ W N SFN SP W N SFN 6 35 SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN SP W N SFN 7 21/44

22 SK W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 SP W N SFN 7 The tilt of the base stations has been set to 0 for fixed reception and -1 (down tilt) for mobile reception. All stations will use the same configuration for radiated power ( W), transmitted frequency (600MHz) and bandwidth (10MHz). 22/44

23 B.2 - Network configurations analyzed The following network configurations have been considered for the base stations and the terminals. Configuration 1 Configuration 2 Configuration 3 Configuration 4 Configuration 5 Configuration 6 Configuration 7 Base stations Omni directional antenna in H and V planes Omnidirectional in H plane and vertical pattern according to ITU-R 1336 Omnidirectional in H plane and vertical pattern according to ITU-R 1336 Omnidirectional in H plane and vertical pattern according to ITU-R 1336 Omnidirectional in H plane and vertical pattern according to ITU-R Optimized configuration V1 Omnidirectional in H plane and vertical pattern according to ITU-R Optimized configuration V2 Omnidirectional in H plane and vertical pattern according to ITU-R 1336 Terminal Fixed antenna according to ITU-BT m AGL Fixed antenna according to ITU-BT m AGL Fixed antenna according to ITU-BT m AGL oriented towards the center of SFN 4 Advanced fixed antenna from Qualcomm 10m AGL Advanced fixed antenna from Qualcomm 10m AGL Advanced fixed antenna from Qualcomm 10m AGL Mobile omni antenna 1.5m AGL The next sections will provide detailed analysis of each configuration except configurations 5 and 6 that are considered in section C. B.3 - Configuration 1 The following maps have been provided in JPG format: - "SFN1...7.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "SFN combination.jpg": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. The analysis of the SFN 4 coverage map is showing that 6.68% of the SFN 4 polygon is covered without interference with 93.32% of interfered area. When considering the SFN combination map made for SFN 4 polygon contour that 99.61% of the area is covered and 0.39% of the area is interfered or not covered. 23/44

24 B.4 - Configuration 2 B Simulation results The following maps in JPG format have been provided: - "BS Pattern V Rx 419_SFN1...7.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BS Pattern V Rx 419_SFN_Combination.jpg": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. - "BS Pattern V Rx 419_SFN4 global coverage map": Combination of all SFN coverage showing where SFN4 is covering and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx 419_SFN4 overlapping coverage map.jpg": Combination of all SFN coverage showing where SFN4 is covering alone, where SFN 4 is covering with another SFN, and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx 419_SFN4 overlapping coverage map_number of SFN received.jpg": Combination of all SFN coverage showing how many SFNs are covering each point plus interference areas. The analysis of the SFN 4 coverage map is showing that 93.3% of the SFN 4 polygon is covered without interference with 6.7% of interfered area. When considering the combination of all SFNs, the interference areas are reduced to 0.38% of SFN 4 polygon with 99.62% of coverage without interference. The analysis of the interfered area is made in the next section. 24/44

25 B Analysis of interfered areas in SFN 4 ploygon Interference areas are located into a basin and is at the edge of SFN 4 & SFN 3 coverage. The table below lists the main signals received inside the interference plot. Callsign SFN # Address Status FSR dbuv/m Pr dbm ToA us Delta TOA Frequency MHz Polar Distance m Azimuth (deg) Tilt (deg) 3650 SFN4 TL Wanted H SFN3 TL MFN interferer H SFN4 TL SFN H SFN4 TL SFN H SFN4 TL SFN H SFN3 TL MFN interferer H SFN3 TL MFN interferer H SFN4 TL SFN H SFN4 TL SFN H SFN4 TL SFN H SFN4 TL SFN H SFN4 TL SFN H SFN3 TL MFN interferer H SFN4 TL SFN H SFN4 TL SFN H Rx antenna (m) It has to be noted that only MFN interference occurs. There is no SFN interference. 25/44

26 26/44

27 27/44

28 Terrain profiles From O (wanted) to the interference area 28/44

29 From 257 (strongest MFN interferer) to the interference area 29/44

30 From 1002 (MFN interferer) to the interference area 30/44

31 From (MFN interferer) to the interference area 31/44

32 From 2594 (MFN interferer) to the interference area 32/44

33 So interference is coming from base stations that are located on high points with visibility or very close to visibility conditions to the interference areas. As detailed in the following table, interference mainly occurs outside urban clutters: SFN 4 Combination coverage Total area km² Urban Clutter area km² Other Clutters area km² Total area covered Urban Clutters covered Other Clutters covered Total interfered and noncovered area Interfered and non-covered area over urban Clutters Interfered and non-covered area over other Clutters Configuration % 99.86% 99.57% 0.38% 0.14% 0.43% Possible solutions are proposed in Part C of this document. B.5 - Configuration 3 In order to have an idea of the TV antennas that will need to be re-oriented in order to receive the LPLT service in SFN mode. The assumption made is that all antennas of all SFNs are oriented towards the center of SFN 4 area. Two maps have been provided in JPG format: - "BS V pattern Rx 419 Oriented_SFN4.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BS V pattern Rx 419 Oriented_SFN_Combination.jpg": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. The analysis of the SFN 4 coverage map is showing that 87.1% of the SFN 4 polygon is covered without interference with 12.9% of interfered area. When considering the combination of all SFNs, the interference areas are reduced to 11.58% of SFN 4 polygon with 88.42% of coverage without interference. Compared to Configuration 2 results (0.38% of interference inside SFN 4 polygon of with 99.62% of coverage without interference), it means that around 10% pf the antennas will have to be reoriented. B.6 - Configuration 4 In order to improve the SFN 4 coverage, the ITU-R BT.419 standard antenna is replaced by a High Performance antenna manufactured by Qualcomm. 33/44

34 The following maps in JPG format have been provided: - "BS Pattern V Rx HP_SFN1..7.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BS Pattern V Rx HP_SFN_Combination.jpg": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. - "BS Pattern V Rx HP_SFN4 global coverage map.jpg": Combination of all SFN coverage showing where SFN4 is covering and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx HP_SFN4 overlapping coverage map.jpg": Combination of all SFN coverage showing where SFN4 is covering alone, where SFN 4 is covering with another SFN, and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx HP_SFN4 overlapping coverage map_number of SFN received.jpg": Combination of all SFN coverage showing how many SFNs are covering each point plus interference areas. The analysis of the SFN 4 coverage map is showing that 95.66% of the SFN 4 polygon is covered without interference with 4.34% of interfered area. When considering the combination of all SFNs, the interference areas are reduced to 0.1% of SFN 4 polygon with 99.9% of coverage without interference. The interference araes are then very limited and covering a very small amount of Urban clutters: SFN 4 Combination coverage Total area km² Urban Clutter area km² Other Clutters area km² Total area covered Urban Clutters covered Other Clutters covered Total interfered and noncovered area Interfered and non-covered area over urban Clutters Interfered and non-covered area over other Clutters Configuration % 99.89% 99.97% 0.10% 0.11% 0.03% The use of High Performance antennas is highly improving the interference problem. B.7 - Configuration 7 Using the same fixed network of base stations, the mobile reception is then analyzed. The following maps in JPG format have been provided: - "BS Pattern V Rx Mobile_SFN jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BS Pattern V Rx Mobile_SFN combination.jpg ": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. 34/44

35 - "BS Pattern V Rx Mobile_SFN4 Global coverage map.jpg ": Combination of all SFN coverage showing where SFN4 is covering and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx Mobile_SFN4 overlapping coverage map.jpg ": Combination of all SFN coverage showing where SFN4 is covering alone, where SFN 4 is covering with another SFN, and where other SFNs are covering, plus interference areas. - "BS Pattern V Rx Mobile_SFN4 overlapping coverage map_number of SFN received.jpg ": Combination of all SFN coverage showing how many SFNs are covering each point plus interference areas. The analysis of the SFN 4 coverage map is showing that 72.18% of the SFN 4 polygon is covered without interference with 22.25% of interfered area and 5.57% of non-covered area. When considering the combination of all SFNs, the interference and non-covered areas are reduced to 24.45% of SFN 4 polygon with 75.55% of coverage without interference. The mobile reception would need to be improved but is already achieving a rather good quality of service at this stage. Part C - Local optimization in difficult areas When considering the coverage results achieved in Configuration 4, the fixed reception is almost perfect inside SFN4 contour, except in the following 2 areas at the border between SFN 3 and SFN 4: 35/44

36 In order to improve the situation, 2 optimization configurations have been studied: Configuration 5 Configuration 6 Base stations Omnidirectional in H plane and vertical pattern according to ITU-R Optimized configuration V1 Omnidirectional in H plane and vertical pattern according to ITU-R Optimized configuration V2 Terminal Advanced fixed antenna from Qualcomm 10m AGL Advanced fixed antenna from Qualcomm 10m AGL C.1 - Configuration 5 A first optimization step has been performed from Configuration 4. The network improvements have been made on the 2 local areas listed above with the following configuration: - " 797" station has been sectorized with 2 sectors with 120 aperture in the horizontal pattern based on ITU-R 1336 standard antenna. One sector pointing to 90 and the other to /44

37 - " 257" station has been sectorized with 2 sectors with 180 aperture in the horizontal pattern based on ITU-R 1336 standard antenna. One sector pointing to 120 belonging to SFN 3 and the other pointing to 300 belonging to SFN 4. 37/44

38 - " 54258" station originally belonging to SFN 3 has been sectorized with 3 sectors, one towards SFN 3 and 2 towards SFN 4 with 120 aperture. Same 120 pattern as above. 38/44

39 Sector pointing to 180 belonging to SFN 3 and sectors pointing to 60 and 300 belonging to SFN 4. - A new station has been added ( W radiated power, 600MHz): Longitude Latitude Altitude Antenna height AGL Callsign SFN ID 4DMS 4DMS (m) (m) Add E N SFN 4 The following maps in JPG format have been provided: 39/44

40 - "BS Pattern V Rx HP_SFN1..7.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BS Pattern V 1336 Optim - Rx HP _SFN_Combination.jpg": Combination of all SFN coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. The analysis of the SFN 4 coverage map is showing that 96.55% of the SFN 4 polygon is covered without interference with 3.45% of interfered area. When considering the combination of all SFNs, the interference areas are reduced to 0.63% of SFN 4 polygon with 99.37% of coverage without interference. Interference on the combination map is mainly around the sectorized antennas due to a front to back ratio that is not enough to remove interference between adjacent sectors belonging to different SFNs. 40/44

41 Compared to Configuration 4, the SFN 4 coverage considered alone is a bit improved, but the coverage without interference in the when considering the combination of all SFNs is a bit worse than the original network. Another improvement is then considered in Configuration 6. C.2 - Configuration 6 Another optimization step has been conducted from Configuration 5 with the following modifications: - Only one sector of original station " 257" station has been considered with 180 aperture pointing towards SFN 3 in azimuth Only the 2 sectors of the 3 made from " 54258" original station are considered. Sector pointing towards SFN 3 has been removed, keeping 2 sectors pointing towards SFN 4 in azimuths 60 and 300 with 120 aperture. 41/44

42 The following maps in JPG format have been provided: - "BS Pattern V Rx HP_SFN1 and 2.jpg": Individual SFN coverage with 2 values. 0 for interference and 1 for coverage without interference. - "BBS Pattern V 1336 Optim - Rx HP V2_SFN3+4_Combination.jpg": Combination of SFN 3 and SFN 4 coverage with 2 values. 0 for interference (no SFN is available without interference) and 1 when at least 1 SFN is covering without interference. The analysis of the SFN 4 coverage map is showing that 97.27% of the SFN 4 polygon is covered without interference with 2.73% of interfered area. 42/44

43 With this configuration, SFN 4 single coverage is improved compared to Configuration 5 but more important, it demonstrates that local optimization is possible by adding sites or reconfiguring sectors that will solve local interference problems. Part D - Overall analysis of the solution studied The study has demonstrated that: As expected, the SFN coverage with the use of LPLT SFN networks and existing mobile sites is perfectly received inside each SFN contours with fixed reception. 43/44

44 With the same configuration of sites used for fixed reception, the results achieved for the mobile reception are encouraging. The quality of service is lower than the one of the fixed reception but could be improved by adding more sites Interference problems are occurring at the border of two different SFNs and are exclusively coming from other SFNs (MFN interference). With the help of 200µs cyclic prefix, there is no intra SFN interference. So, with the use of an advanced fixed antenna, interference levels are highly reduced, but not completely removed in some local areas. And interference areas are mainly located outside urban Clutters. Finally, we have seen that adjusting SFN coverage contours to the administrative contours with the help of local optimization, as seen in Configuration 6, is necessary. So that adding sites where the coverage is poor and interfered is a good option. And using sectorized sites with appropriate azimuth orientation is also a good way to reduce local interference problems. 44/44