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18 June 2008


RFMD unveils 400W GaN HPA for pulsed S-band radar

At this week’s IEEE MTT-S International Microwave Symposium (IMS 2008) in Atlanta, GA, USA, RF Micro Devices Inc of Greensboro, NC, USA has unveiled a 400W high power amplifier (HPA) designed for air traffic control radar and ship-borne or ground-based pulsed S-band surveillance radar applications.

In radar applications the 400W GaN HPAs operate over a frequency range of 2.9-3.5GHz from a 65V supply, delivering a power gain of 10.5dB. Placed in a thermally efficiency, ceramic hermetically sealed package measuring only 24 x 17.4 mm, they deliver power density and size advantages over competing silicon bipolar technologies. RFMD says that its GaN process technology provides a larger bandwidth at a higher operating output power than silicon bipolar while maintaining a drain efficiency of 50% across the band.

In S-band radar applications HPAs are combined in larger 2.5KW ‘pallet’ amplifier assemblies with as many as eight or more HPAs in each pallet. Traveling wave tubes (TWT) technology, traditionally used in these applications, are prone to reliability issues, resulting in field failures and expensive replacement costs. With a mean-time-to-failure (MTTF) goal of 1,000,000 hours at a junction temperature of 200 degrees C, RFMD says that its GaN technology will deliver superior reliability, resulting in a considerably lower total cost of ownership.

“RFMD is committed to delivering a portfolio of highly competitive and compelling components for the aerospace & defense (A&D) marketplace,” says Jeff Shealy, VP and general manager of RFMD’s Aerospace & Defense business unit. “RFMD’s advancements in GaN process technologies are paving the way for a broad range of components for radar and other high-power applications,” he adds. “Additionally, our longstanding relationships in the A&D market enable RFMD to engage key customers to evaluate these state-of-the-art process technology innovations.”

RFMD is presenting additional information on the 400W GaN HPAs in a technical session at IMS 2008.

RFMD launches first 5.8GHz ISM-band transceiver with integrated PA

RFMD has also made available samples of what it claims is the industry’s first 5.8GHz ISM-band transceiver with an integrated power amplifier. Pre-production quantities will be available in third-quarter 2008 in a 6mm x 6mm x 1mm, 40-pin QFN package.

The ML5805 is a low-IF, frequency shift key (FSK) transceiver designed for operation in the license-free 5.8GHz industrial, scientific and medical (ISM) band (and follows the ML2726 low-IF FSK transceiver for the 2.4GHz ISM band, launched at the beginning of May for applications including game controllers, PC peripherals, automatic meter reading, security systems, telemetry and point-of-sale vending equipment). Proprietary point-to-point and point-to-multi-point radios using 5.8GHz ISM-band transceivers are increasingly being implemented in consumer applications such as wireless audio, wireless video and data connectivity.

The ML5805 integrates the power amplifier (PA) and low-noise amplifier (LNA) with the transceiver architecture onto a single chip. RFMD says that its unique design provides radio designers with ease of implementation and a minimal external bill-of-materials (BOM) count as well as improved time to market for original equipment manufacturers (OEMs). Additionally, the ML5805 provides the flexibility to optimize each application by offering five, digitally selectable data rates (from 576Kbps to 2.048Mbps), allowing it to serve a wide range of applications and further accelerating time to market by enabling broadly applicable 5.8GHz radio platforms.

The ML5805 is the first product to incorporate RFMD’s proprietary FastWave microcontroller technology, which improves performance through value-add features including self-alignment of the low-IF receiver and phase-locked loop (PLL) detection and control. FastWave also provides flexible user-specific application configurations by allowing modifications via a three-wire serial interface to transceiver control, calibration and interface algorithms. The ML5805 therefore eliminates the cumbersome mass-production tuning process necessary with competing transceivers.

“With the implementation of our proprietary FastWave microcontroller technology, the ML5805 delivers incremental benefits to designers and OEMs in time savings and simplified design,” claims Alastair Upton, general manager of RFMD’s Broadband and Consumer business unit.

Designed to target a significantly expanded range of data-rate applications, Upton says that the ML5805 improves upon the performance characteristics of the firm’s existing 5.8GHz ISM-band transceiver (the 1.5Mbps data-rate ML5800), which has enjoyed favorable design activity into multiple proprietary wireless connectivity applications, including wireless speaker applications by Eleven Engineering. RFMD is demonstrating a high-performance Eleven Engineering audio application at IMS 2008.

Technical features of the ML5805 include:

  • an integrated PA delivering +21dBm typical output power;
  • improved receive (Rx) sensitivity of -97dBm at 0.1% bit error rate (BER);
  • improved fractional-N synthesizer performance with 30Hz resolution;
  • three-wire serial control interface; and
  • self-calibrating voltage-controlled oscillator (VCO) and filters that eliminate tuning using FastWave microcontroller technology.

See related item:

RFMD halting transceiver development and selling GPS business

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