RF transceivers target small-form-factor mobile WiMAX

With today's release of the AD9354 and AD9355 WiMAX transceivers, Analog Devices Inc. has integrated analog-to-digital converters (ADCs), DACs, and real-time control and calibration loops in a single chip. This approach consolidates the analog functionality in the transceiver chip, enabling digital modem manufacturers to avoid a mixed signal manufacturing process, and instead go all digital.

The two transceivers are essentially identical, except that each serves a different frequency band. The AD9354 operates from 2.3 to 2.7 GHz, serving markets primarily in Japan, Korea, and North America. The AD9355, on the other hand, ranges from 3.3 to 3.7 GHz, serving markets primarily in Europe, India, and China.

As a second generation to ADI's AD9352 and AD9353 integrated WiMAX transceivers introduced last year, the AD9354 and AD9355 were optimized to consume less power in a smaller package than other transceivers in their class. In addition, they include an additional receiver path for multiple-input multiple-output (MIMO) support.

Tom Gratzek, ADI's WiMAX transceiver business director, explains how the new products differ from their predecessors: “This year, we are responding to our customers evolving needs, concentrating on smaller form factors. We also added a second receiver to meet carrier MIMO requirements. In order to keep the end form factor very small, we take the data from the four different ADCs into the same interface; this way we did not have to add pins.”

The AD9354 and AD9355 transceivers integrate two direct-conversion receivers and use the industry-standard JESD207 digital interface. The architecture supports autonomous automatic gain control (AGC), transmit power control (TPC) and calibration routines. The closed-loop power control enables 1-point factory calibration of transmit power.

Now, to the specs! Transmitter error vector magnitude (EVM) is -38dB at 0dBm output power. The AD9354 and AD9355 support channel bandwidths of 3.5, 4.375, 5, 7, 8.75 and 10 MHz. The devices feature a 3.25-dB noise figure (NF) and 60dB signal-to-noise ratio (SNR) for the ADCs.

The AD9354 and AD9355 mobile WiMAX transceivers are sampling now, with production quantities expected in Q4 2007. The devices are priced at $11.45 per unit in sample volumes. The AD9354 and AD9355 are housed in an 8 mm x 8 mm, 64-lead LFCSP (lead-frame chip-scale package). Click here for more information, or visit or call 1/800-262-5643.

Related Articles

0 comments on “RF transceivers target small-form-factor mobile WiMAX

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.