Electronic Design

Spread-Spectrum Transceiver Makes Low-Data-Rate Wireless Painless

Even the most experienced engineer cringes at radio design. Yet more products are going wireless simply because it sells. One way around this is to buy an entire OEM wireless module to build into forthcoming wireless products.

L.S. Research's XETI transceiver, a frequency-hopping spread-spectrum (FHSS) data modem, operates in the unlicensed industrial-scientific-medical (ISM) band of 902 to 928 MHz. Based on the Xemics XE1202 transceiver chip, the chip has 1023 hop frequencies. Its Texas Instruments MSP430 embedded controller can be programmed to customize the unit to the application. The unit operates from 3 V and puts out 500 mW of RF power. The range obviously varies given the local environment, but it can be as far as several miles outdoors under ideal line-of-sight conditions. It consumes 21 mA in the receive mode and 5 mA in standby.

The XETI's maximum data rate is 115 kbits/s. Modes of operation include point-to-point or point-to-multipoint. Designers can network up to 65,000 units with individual ID codes. Typical applications include industrial data acquisition, sensor networks, and almost any remote monitoring and control job. The Federal Communications Commission will fully certify the unit, which costs less than $100 in small quantities.

• L.S. Research Inc. • www.lsr.com (772) 221-0320
• Xemics • www.xemics.com +41 32 720 5562

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