What are the TV white-spaces?
TV White Spaces (TVWS) are vacant frequencies made available for unlicensed use at locations where spectrum is not being used by licensed services. This band is currently used by Digital Terrestrial Television (DTT) and Program Making and Special Events (PMSE) users.
“White Space technology will work in a similar way to Wi-Fi, which uses a wireless router to send and receive information to other wireless devices. The main difference is that the White Space router – or “master” device as it is known technically – will first need to consult a list of databases hosted online. It will notify one of these databases of its location and update it on a regular basis. The database will then return details of the radio-frequencies and power levels it is allowed to use. This will ensure that the devices do not interfere with existing licensed users of the spectrum, which include Digital Terrestrial Television and wireless microphone users.”
Enhanced Wi-Fi: The majority of current Wi-Fi devices operate in spectrum at 2.4GHz. White Spaces could provide new capacity, while boosting the range of devices, potentially enabling Wi-Fi networks that stretch across towns and cities. This is thanks to the lower frequency of TV White Spaces (typically between 470 and 790MHz).
Rural broadband: White Spaces could be used to provide rural locations with broadband services. In practice, this could be achieved by building a network of transmitters that use White Spaces to link remote houses and villages to larger towns that are already connected to the internet. Trials are currently being undertaken by industry to test this on the island of Bute, Scotland.
Machine-to-Machine Communications (M2M): A relatively new area of innovation called Machine-to-Machine Communications allows information to be exchanged between devices. Many experts believe that in the coming years billions of devices will be able to connect wirelessly and via the internet for a range of applications. White spaces could be used to wirelessly transmit this information, using its additional range to reach deep inside buildings. This could be especially useful for wirelessly measuring utility meters in consumers’ homes – just one of a wide number of potential applications. Other examples include using White Spaces to keep an inventory of stock owned by a business, or making it easier for scientists to conduct research by automating the measurement of different readings.
The UHF TV band (470-790 MHz) and its users
ATDI announces new White-space features in ICS suite.
Since 1997, ATDI supports White-Spaces in ICS telecom (3.5 GHz band, Teledesic and Skybridge projects…). Now, ICS suite allows you to process the complete workflow and publish the data Online.
TVWS calculations and Management with ATDI tools
ICS suite white-space features:
. DTT coverage
. Reserved channels
. Allotments, Assignments, PSME, International coordination, Protected areas (polygons)
. DTT white-space calculation
. TVWS availability calculation
. Available Spectrum maps
. WSD channel assignment
. WSD to DTT interference calculation
. Data storage:
. WSD class
. Permitted power level
. Online access
White-spaces are managed both locally and in the Cloud thanks to ICS Manager
. DTT protected area calculation
. WSD availability map calculation
. Interference WSDs vs WSDs and WSDs vs DTT
. Import TVWSD availability maps and tiling
. Web service validations
. WSD checking
. Status of data in the Cloud
. Map tiles (WMTS server)
. Web services to communicate with WSD (location, QoS, Traffic)
. Import WSDs from Cloud (scenarios)
White space map calculation (multi-technologies):
. Devices or Routers vs Licensed service areas (C/I mode)
. Licensed services vs Devices or Routers (IRF and C/I modes)
. Licensed services vs earth Satellite Rx (GSO, NGSO, Constellations)
. Devices vs Devices or Routers vs Routers or Devices vs Routers (IRF mode)
. Devices or Routers vs Polygons or Routes (PFD)
From UKPM files (from 0.01 m to 100 m resolution)
. LTE vs DTT
. WSD vs DTT
. Multiple log-normal signal calculator (Schwartz & Yeh / Fenton-Wilkinson)
. UKPM household automatic update
. Up to 100 000 interferers (base stations) by DTT channel
. Up to 2 000 000 interferers (WSDs) by DTT channels
WSD vs DTT features:
. Large choice of propagation models (outdoor, indoor, mixed outdoor/indoor, Full 3D)
. Multiple resolution maps (from 0.01 m to 1000 m)
. White-space devices: Class 1, 2, 3, 4, 5
. Rejection: ETSI EN 301 598 or user defined
. Household distribution and filter
. WSD distribution
. Bandwidth ratio
. User defined C/I required and NFD matrices
. DTT white-space maps
. TVWS availability maps (C/I, permitted power levels)
. WSD interference (WSDs vs DTT receivers and DTT transmitters vs WSDs)
. Spurious emissions
. Interference analysis: Multiple scenarios
. Rx antenna discrimination (ITU-R 419, OET69, User defined) (DTT receivers)
. Automatic DTT selection (up to N+- 15)
. Foreign DTT transmitters are taken into account (BRIFIC online access)
. Offline and Online Worldwide database (Location, Channels, Power levels, WSD classes)
. WSD location by coordinates or addresses
. Export WMAS (Google map, Bing Map, OSM), EPSG:4326…
. Web services
Export data formats:
. Matrices (form 0.01 m to 1000 m resolution)
. Google Earth
. Cloud SQL Azure
- For a given location (address, coordinates, click on map…)
. List of available channels and max power level by channel
- Coverage maps per channel
- Protected maps per channel
- Tx per channels
Cloud Map Storage (Windows Azure):
- For each point:
. List of available channel(s)
- For each channel
. Max power level by WSD class
Platform overview for WSD management
Map comparison (Spectrum bridge vs ATDI)
Spectrum Bridge map (Channel 32 Singapore)
Map comparison (Google vs ATDI)
Google Spectrum TVWS availability map (USA)
ATDI protected area map (Channel 28 Oman – WSD 0.22 W EIRP – 100 m resolution)
White-Space calculation example: Oman Channel 39:
WSD maps (Channel 39 – Oman – 100 143 225 WSD locations from 13 to 23 dBm and from Class 1 to 5 – 3 602 600 DTT receivers - map resolution: 100 m
Scenario: WSD 0.22 W max outdoor, Dynamic 10 dB (from 23 dBm to 13 dBm), Classes 1 to 5, DTT map: all servers, Rejection up to N +/-3 .
DTT map (all channels)
Channel 39 – Protected area (servers)
WSD availability map (channel 39) – ITU-R 452:
Blue area = exclusion zone
Green areas = restricted zones (plus Power level constraints)
Brown area = OK
Available Spectrum Map
DTT protected area maps and WSD availability maps are calculated in ICS telecom.
The WSDB is managed by ICS manager and accessible via Web service.
ICS manager hosts the TVWS availability tile maps (WMTS) and perform real-time checking.
WSD interference are performed every time a new WSD is ON (power sum, log-normal sum).
Start and End “switch ON” periods are managed by the system.
ICS online allows you to display DTT protected area maps, TVWS availability maps, WSD locations (including channels and power levels + info), provides a form to enter new WSD (technical parameters, Class, location…).
DTT maps for all countries using BRIFIC or more accurate data if available (or both: i.e. Brific for borders and operator/regulator data for the target country)…
BRIFIC is accessible online thanks to ICS online and is updated twice a month.
WSD application form
WSDs transactions (IN/OUT): Location, QoS, Traffic, Power levels, Channels…