DirectBand

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DirectBand™ is a North American wireless datacast network owned and operated by Microsoft. It uses FM radio broadcasts in over 100 cities to constantly transmit data to a variety of devices, including wristwatches and home weather stations.

1 How it works
- 1.1 Not like RDS
- 1.2 Push network
2 Receivers
3 Microsoft design
4 FM subcarrier usage
5 See also
6 External links

[edit] How it works

DirectBand uses the 66.75 kHz subcarrier leased by Microsoft from commercial radio broadcasters. This subcarrier delivers about 12 kbit/s of data per tower, for over 100 MB per day per city. Data includes traffic, sports, weather, stocks, news, movie times, calendar appointments, and local time.

[edit] Not like RDS

It is important to note that DirectBand does not use the RDS (Radio Data System) subcarrier. RDS is a different and lower bandwidth (~1.18 kbit/s) subcarrier primarily used for radio station information and traffic.

[edit] Push network

DirectBand is a push network -- new content is delivered every 2 minutes. For fault tolerance reasons most cities have two broadcast towers delivering the same content.

[edit] Receivers

There are a variety of DirectBand receivers. All use a small (2.794 mm x 2.794 mm x 860 µm) radio receiver and an ARM7-based processor.

[edit] Microsoft design

DirectBand is a product of the Smart Personal Objects Technology (SPOT) team at Microsoft. MSN Direct is the consumer brand that Microsoft uses for devices that receive content from the DirectBand network.