Frequency-Hopping Wireless UART Chipset for Short-Range Wireless Applications

(Product News, 13 Jul 2005)

Texas Instruments has introduced a frequency-hopping spread spectrum (FHSS) wireless universal asynchronous receiver/transmitter (UART) chipset for the unlicensed United States 902 MHz to 928 MHz Industrial, Scientific and Medical (ISM) radio frequency bands. The Dolphin chipset is a wireless interface suitable for a variety of consumer, industrial and commercial applications, with the hardware, software/firmware and support designers need to integrate a low-data-rate wireless link into their systems. The chipset offers the features of a FHSS system to combat signal interference from other devices, an issue for short-range wireless equipment due to the growing popularity of the unlicensed bands. In addition, FHSS enhances message privacy, provides better transmission range and decreases the probability of transmissions being intercepted by other devices, according to the company. Designers gain a true data-in/RF-out and RF-in/data-out chipset, including the TRF6903 single-chip, multi-band radio frequency (RF) transceiver and the DBB03 digital baseband application-specific integrated circuit (ASIC). All aspects of data management and frequency hopping are implemented in firmware on the DBB03, which includes the PHYsical, MAC and data link layer. A simple external host microcontroller (MCU) performs all system functions related to the end application. This allows the designer to select the external host from an array of catalog MCUs. Since the interface between the DBB03 and the host MCU is a simple UART, end applications treat the RF link as a peripheral, making it flexible, scalable and easy to implement. Fast frequency-hopping reduces power consumption and enables fast acquisition time of 70 ms for 50 channels. Two reference designs are available: high transmit power (+23 dBm) for a range up to 1 mile, and low transmit power(+7 dBm with range up to 0.2 mile. The chipset is priced at $4.50 in 1,000-unit quantities.