Embedded Systems Show - August 2002

RF 'wire-replacement' for M2M applications

Comtech has announced the release of its first wireless communication module, aimed at gathering machine-to-machine (M2M) data over a local area. OEM-RF-8 acts as a wire-replacement by transporting serial data over an RF medium using the unlicensed 868-870MHz frequency bands.

OEM-RF-8 is a transceiver module, which supports half-duplex transmission and reception of data over RF. It is ideally suited to transporting half-duplex protocols like Modbus and provides a TTL serial interface, supporting TxD, RxD, RTS, CTS and DCD. Potentially a direct replacement for cables, it can work in buffered mode, where serial data is buffered and encapsulated into packets with a CRC prior to transmission over RF. This adds a small delay to the data transmission, but offers increased resilience to noise through CRC checking. Alternatively it can work un-buffered, so data is transmitted with minimal delay. This suits large polling networks where protocols operate timeouts.

OEM-RF-8 supports data rates to 9600bps, and is compliant to ETSI 300220, offering a typical ERP 20mW (+13dBm) at 50½ termination. OEM-RF-8 is generic to suit any application, however it is particularly powerful when combined with Comtech's own technology.

Comtech
j133@industrialnetworking.co.uk