WiMax SOC supports TDD and FDD flavors, channel agility
By Maury Wright -- EDN, May 12, 2005
Fujitsu Microelectronics has formally announced its WiMax SOC (system on chip) at the Broadband Wireless World show in Las Vegas last month after a year or so of preliminary presentations on WiMax technology and the company’s intentions of pursuing silicon opportunities in the market. Fujitsu is the second big name in WiMax silicon, following Intel (www.intel.com) into the market, along with smaller players, such as PicoChip (www.picochip.com) and Wavesat (www.wavesat.com). For more background on WiMax, see “WiMAX wireless broadband: Fixed-flavor questions abound, mobile lurks,” EDN, March 31, 2005, pg 44.
Fujitsu’s MB87M3400 SOC integrates an OFDM (orthogonal-frequency-division-multiplexing) 256 PHY (physical layer) that supports channels ranging from 1.75 to 20 MHz. Moreover, the chip supports both FDD (frequency-division-duplex) and TDD (time-division-duplex) modes of operation—an option that the IEEE 802.16 d WiMax standard allows.
The mixed-signal IC employs two processing cores to implement the MAC (media-access controller) and PHY baseband processor. An ARM 9 core handles the upper portions of the MAC layer along with scheduling, drivers, protocol stacks, and user software. Meanwhile, a combo RISC/DSP core from ARC handles the computationally intensive lower portions of the MAC layer. The chip also includes DES (Data Encryption Standard) and AES (Advanced Encryption Standard) encryption engines, a memory controller, an Ethernet controller, a data converter, and an external processor interface.
Fujitsu offers a complete reference design for the MB87M3400 and plans to get the WiMax Forum (www.wimaxforum.org) to certify the design. The chip costs $45 (1000).
Fujitsu Microelectronics, www.fujitsu.com/micro/wimax.
