ADI releases WiMAX terminal RF transceiver to reduce costs

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ADI releases WiMAX terminal RF transceiver to reduce costs [Copy link]

ADI releases WiMAX terminal RF transceiver to reduce costs

Analog Devices, Inc. (NYSE: ADI), a leading global supplier of high-performance signal processing solutions, demonstrated two RF transceivers for Worldwide Interoperability for Microwave Access (WiMAX) terminals at the WiMAX World Summit in Boston, USA, from October 10 to 12, which will help reduce costs and promote large-scale deployment of broadband wireless access. Based on the IEE 802.16 standard, WiMAX terminals provide wireless broadband connections and are a low-cost alternative to wired connections such as DSL and cable modulation. With ADI's advanced data conversion and RF signal processing expertise, these two new transceivers integrate high-performance on-chip data converters and provide excellent RF performance, enabling WiMAX terminal solutions to meet the requirements of large-scale deployment and low cost. Excellent RF performance ensures extended coverage and improved service quality - important factors that enhance the user experience and help promote consumer adoption.

Unlike traditional solutions that implement analog functions on separate devices or integrate data converters on ASICs, the AD9352 and AD9353 RF transceivers utilize the "smart partitioning" concept first proposed by ADI, integrating all analog signal processing technologies - analog-to-digital converters (ADCs), digital-to-analog converters (DACs), and RF functions on a single chip. This helps to use more cost-effective fine-wiring processes, such as 90 nm or 65 nm to produce digital baseband chips. The transceiver can be directly connected to the digital modulator through the ADI/Q? digital I/Q interface. This digital interface is a simple parallel CMOS digital I/O interface that has been adopted by many digital modulator manufacturers.

"Analog Devices is the first company to introduce an RF CMOS direct conversion WiMAX transceiver that combines high integration and performance, and provides seamless connectivity to the digital baseband using the ADI/Q digital I/Q interface," said Bernard Aboussouan, vice president of marketing and business development at Sequans Communications, a leading global provider of fixed and mobile WiMAX hardware and software. "We chose to work with Analog Devices and use the ADI/Q digital interface in our 802.16e standard digital baseband product, the SQN1110. We are confident that the combination of ADI's WiMAX transceiver and our digital baseband products will provide WiMAX terminal manufacturers with a solution that meets their price, performance and time-to-market needs."

"WiMAX continues to gain industry support, with recent commitments from many operators around the world and in North America to build nationwide WiMAX networks," said Dave Robertson, product line director, High Speed Signal Processing Division, Analog Devices. "By introducing products like the AD9352 and AD9353 transceivers, Analog Devices is facilitating large-scale deployment of WiMAX and working to reduce costs and improve performance."

Highly integrated RF transceiver

The AD9352 and AD9353 are fully integrated direct-conversion transceivers for WiMAX (based on the IEEE 802.16 standard) wireless network systems. They provide a complete RF and mixed-signal system in a single chip. The dual-band AD9352 operates in the 2.3-2.7 GHz and 4.9-5.9 GHz bands, while the single-band AD9353 operates in the 3.3-3.8 GHz band. These two transceivers cover most of the licensed and unlicensed frequency bands worldwide.

The two transceivers integrate 12-bit resolution, 60 MSPS sampling rate ADC and DAC, with intelligent system functions such as automatic calibration, automatic gain control, transmit power control, support for automatic frequency control, and auxiliary ADC and DAC for system monitoring. The built-in converter and intelligent system functions reduce the need for real-time signal processing between the modulator and the transceiver, thereby greatly simplifying the development and support of the RF driver. The two transceivers also integrate a high-sensitivity direct-conversion CMOS receiver and a band-selectable baseband filter. A low phase noise local oscillator (LO) channel is provided by integrating a fractional-N frequency synthesizer. In addition, in order to reduce system cost, the built-in crystal oscillator replaces the expensive voltage-controlled temperature compensated crystal oscillator (VCTCXO).

Excellent RF performance

The two devices offer an excellent noise figure of 3.5 dB and an adjacent channel power rejection ratio (ACPR) that is 8 dB higher than the IEEE 802.16 standard requirement. The device's highly linear transmit channel provides excellent spectral purity and an error vector magnitude (EVM) of –37 dB at 0 dBm output power. The transmit power is detected by a precise power detector and has automatic control capability with a 60 dB range and 0.25 dB steps.