Startup's processors support multiple wireless protocols

Startup's processors support multiple wireless protocols
By Junko Yoshida, EE Times
December 8, 2000 (6:04 a.m. EST)
URL: http://www.eetimes.com/story/OEG20001206S0030

PLEASANTON, Calif. — Startup Embedded Wireless Devices Inc. will tackle the interoperability issues that dog a number of potentially conflicting wireless standards when it begins to roll out early next year a family of controllers that can handle multiple wireless links simultaneously. EWD's chips are designed to run a mix of voice and data traffic across Bluetooth, 802.11a/b, Digital Enhanced Cordless Telecommunications, HyperLAN II and HomeRF links.

"You need wireless solutions that can convert data, route data to different end points over different protocols," said Peter Petersen, vice president of engineering at Embedded Wireless Devices (Pleasanton, Calif.), a company with engineering roots in Denmark.

At a time when many wireless networking standards are expected to coexist within a single home, devices capable of "supporting multiprotocols are almost a necessity," said Allen Nogee, senior analyst for wireless component technology at Cahners In-Stat Group.

EWD is launching its e8000 Valhalla family of chips able to process multiple baseband protocols — including Bluetooth, 802.11a/b, DECT, HyperLAN II and HomeRF. At the heart of the devices lies the company's proprietary eMOS multitasking operating system. Designed for fast context switching, eMOS "enables simultaneous protocol support switching from one protocol to another," according to Ken Kristie, director of corporate marketing at EWD. At the physical level, that switching takes only "nanoseconds, which would appear to the user as being simultaneous," he said.

The chips in the Valhalla family essentially serve as "routing engines" for a variety of wireless multipoint devices such as residential gateways or wireless Web pads, according to Petersen. Such gateway products can control household functions like thermostat settings, garage door operation, security, and Internet access from a cordless phone set or base.

Interface to an RF module is implemented in software s o that the new baseband chips can be connected to virtually anybody's RF modules, according to Kristie. EWD offers a reference design that show OEMs how to connect EWD's baseband chips with the 2.4-GHz RF modules of either Infineon or National Semiconductors, Kristie said.

Multiplayers

As already seen in multiprotocol processing solutions developed by Mobilan, Silicon Wave and Intersil, a number of chip companies are pursuing solutions that can operate in multiple protocol environments.

Naturally, there are cost and technology issues associated with multiprotocol solutions, said Joyce Putscher, director of the consumer and converging markets and technologies group at Cahners In-Stat Group. The technical challenges "depend on whether it is 'dual-mode' or 'simultaneous' operation," she said. "Cost would be the challenge, especially if you have to use two separate solutions for two protocols."

While competitors' s olutions are focused on the combination of Bluetooth and 802.11b processing, Embedded Wireless Devices is taking a more general approach for multipoint wireless devices. The company's focus is also on affordable solutions for consumer system OEMs.

Besides Embedded Wireless Devices' baseband processors' ability to work with other companies' RF modules, "Our protocols are configurable," said Kristie. "We offer a total system solution tailored for Asian system OEMs looking for high volume and low cost wireless chips," he said. An unnamed tier-one Japanese consumer system OEM has already signed up to use one of the e8000 Valhalla family chips for a wireless home gateway product, according to Richard Murphy, vice president of worldwide sales and marketing at EWD.

Founded in 1995, the startup has already accumulated ample experience in designing chips for the DECT-based cordless phone market proliferating in Europe and Asia. DECT, designed for voice and multimedia traffic, is a digital radio access standar d for cordless communications in residential, corporate and public environments.

Curiously, the Valhalla family's core hardware architecture — a combination of the company's proprietary DSP and microprocessor — and eMOS both have roots in DECT solutions originally developed in Denmark by Embedded Wireless Devices' founding engineers. While leveraging its DECT expertise, the company has set a goal to help traditional DECT phone manufacturers quickly upgrade their cordless phones to be able to handle multiple wireless protocols at a lower cost.

The operation of the proprietary eMOS is optimized for the company's DSP/microprocessor hardware architecture. The eMOS, designed for fast context switching — within a few clock cycles — allows the processor to perform 160 simultaneous tasks, according to Petersen. In receiving data from other wireless devices on a 2.4-GHz RF, the Valhalla family chips first recognize the message of each unit, its ID tag and coding scheme, then provide base band processing accordingly. Protocol processing occurs one unit at a time, but can be quickly switched to another protocol. A highly secure scheduling kernel controls the multitasking operating system. The kernel handles "task synchronization, inter-task message handling and timer-event transmission," according to Petersen.

The eMOS operating system also manages power consumption, system interrupts, and memory usage. It is flexible and customizable to allow for control over power, and may be used to set the speed of the hardware, the speed of each task and the priority of tasks running on the DSP/processor core. EMOS also offers a C-language compatible application programming interface and debugging module.

Embedded Wireless System is offering two Valhalla chips. The e8720e is a wireless system-on-chip device that features the company's proprietary 32-bit processor running at 60 MHz, built-in Bluetooth 1.0 baseband controller and two high-bandwidth baseband controllers for 802.11b and other high-sp eed protocols. A TCP/IP protocol stack and Web browser application software reside on the processor. The company's 32-bit fixed-point DSP provides processing for voice as well as compressed audio and video.

Flash access

The chip comes with 1 Mbit (8 x 128 kbytes) of on-chip flash memory, offering access speeds of less than 20 ns for program and data storage. "To achieve the right speed and the right processing in multiprotocol environments, embedded flash is a must," said Petersen. "All the time critical program code can be accessed within 20 ns or faster."

The e8715e Wireless System is optimized for digital cordless spread-spectrum telephones, digital recorders and computer peripherals. The chip, integrated with embedded flash memory, features a 16-bit microprocessor running at 40 MHz, and two high-bandwidth baseband controllers for 802.11b, DECT, and other high-speed protocols. Similar to the e8720e, a TCP/IP protocol stack and Web browser application software reside on the processo r.

Both e8720e and e8715e are manufactured at United Microelectronics Corp. in Taiwan using a 0.25-micron process. The e8720e, in a 128-lead TQFP, will be available in the second quarter of 2001 "at less than $6.50," according to Murphy. The e8720e, priced at "less than $5.00 in high volume," will become available in the first quarter of 2001.