The benefit of Bluetooth in AMR
Bluetooth is one of the leading wireless standards in home and SOHO (small office/home office) connectivity. In addition, it could well address present and future applications for purposes other than simply replacing connection cables. In the example described here, Bluetooth is enabled with the WAVENIS™ technology to radically improve the business case for AMR.
Bluetooth focuses on low power portable or mobile applications. However, the energy consumption of a typical Bluetooth solution remains incompatible with long-life battery powered equipment such as remote meter reading modules.
In order to get round this Coronis Systems has developed a patented technology, WAVENIS™, capable of extending the capabilities of Bluetooth equipment to ultra-low power (ULP) applications such as AMR. This has two major advantages.
First, the increasing number of proprietary communication systems for the home and its immediate environment (AMR, security, home automation, etc) raises serious interoperability and compatibility problems. Extended capabilities for an established standard like Bluetooth should bring a guarantee of durability and reliability.
Second, Bluetooth will feature increasingly in broadband residential gateways and set top-boxes implementing ADSL modem, cable TV or satellite systems, performing its prime function of cable replacement. If residential gateways integrate the WAVENIS -extended Bluetooth, they can then be incorporated in ULP applications.
This business model is more efficient than deployment of dedicated metering gateways, even when extra home services are added. Broadband residential gateways indeed emerge as the only clear and viable business model today, since users are prepared to pay for the proposed services (pay-per-view, high speed Internet, etc.). Since Bluetooth-enabled gateways are inherently able to read ULP devices, the cost of a fixed AMR network infrastructure can be saved.
The WAVENIS technology is well suited to applications, like AMR, that require an independent power source and long range. WAVENIS devices are seen as slaves on a Bluetooth piconet and do not interfere with the network operation. They use physical and MAC (Medium Access Control) layers very similar to Bluetooth, but with a low operating power consumption (below 0.015 µA).
As a Bluetooth extension, WAVENIS devices can be read by the master of a piconet through regular Page Access and Page Scan procedures, but without maintaining any kind of beacon-based synchronisation when they are in park mode. Their access time is around one second. But unlike standard Bluetooth equipment, WAVENIS devices can be located up to few hundred metres from the master.
The dramatic consumption and range improvements have been achieved by trading off the data rate. The throughput is limited to about 12 kbit/s. Otherwise, like Bluetooth itself, WAVENIS devices use spread spectrum frequency hopping (FHSS) and once connected, they keep the same access. WAVENIS can operate not only in the 2.45 GHz band, but also in the European 868 MHz band and the US 915 MHz band.
The Coronis is)FlowMeter system features AMR-dedicated WAVENIS devices that can be read from a hand-held computer (HHC), VAN or residential gateway, integrating either a WAVENIS-extended Bluetooth module or a stand-alone WAVENIS communication module (if full Bluetooth functionality is not required on the concentrator).
The latter case is a classic AMR arrangement, but if the concentrator (typically the HHC or residential gateway) does integrate Bluetooth, there is no additional cost entailed in affording read capability of is)FlowMeter modules.
A broad industry consortium has been formed by companies interested in ULP-extended Bluetooth capabilities, with special emphasis on metering applications. This provides a sound basis for Coronis’s current partnership on the supply of both base-band and front-end Bluetooth circuits implementing native WAVENIS technology.