|
 |
networkZONE Products for the week of November 17, 2008
Atheros Communications Says…
Align Technology Leverages 802.11n 1-Stream Specification to Provide Upgrade from Legacy 802.11g
Comprehensive 1-Stream Portfolio Enables Align Ecosystem Consisting of Value-Class Home Networking Equipment, PCs and Consumer Electronics
Atheros Communications, Inc. has announced the first members of its Align product family, the industry’s most complete portfolio of wireless LAN (WLAN) solutions based on the IEEE draft 802.11n 1-stream specification. The single-stream feature enables a new class of Wi-Fi devices that deliver performance enhancements over the existing 802.11g technology, at comparable price points. Align solutions are also forward compatible to higher-performance, multi-stream, MIMO-based 802.11n – providing the optimal upgrade path for value-class WLAN products.
Consumers who move from 802.11g to products based on Align 1-stream technology will experience enhanced performance in their home networks. Align solutions deliver up to 150 Mbits/s PHY rates, and leverage the efficiencies of the 802.11n media access control (MAC) technology to achieve actual throughput levels up to five times that of legacy 802.11g. The higher throughput of 1-stream products improves network efficiency by occupying the wireless channel for shorter periods than slower 11g devices – reducing congestion and increasing capacity for additional wireless devices. Align products employ optional features of the 11n specification and Atheros’ advanced radio design techniques, to effectively double the wireless coverage versus legacy WLAN solutions.
Initial Align solutions target the low-cost notebook, netbook, home networking and consumer electronics (CE) markets, enabling end-to-end, 1-stream connectivity for highly reliable and power-efficient WLAN operation. With its significant 802.11g footprint among leading PC and networking equipment manufacturers, Atheros is enabling a rapid transition from legacy WLAN to Align 1-stream technology.
The Atheros Align portfolio is the ideal performance and value complement to the company’s XSPAN family, which was launched in 2006 and is now the most widely adopted 802.11n technology worldwide. Based on the 2-stream, MIMO-enabled 802.11n specification, today’s XSPAN solutions deliver up to 300 Mbits/s PHY rates per band, providing the best user experience for advanced multimedia networking. Together, XSPAN and Align comprise Atheros’ new-generation WLAN product portfolio, which offers customers performance and price options to address the complete range of throughput and coverage requirements of today’s wireless PC and home networking products.
Align for PCs: Atheros AR9285
The Atheros AR9285 single-chip PCI Express (PCIe) solution enables PC OEMs to cost-effectively migrate their 11g-based notebooks to the enhanced, future-proofed performance of Align. This solution targets the growing value PC market segment consisting of sub-$500 notebook and netbook products. Align is the ideal technology for PC users seeking robust throughput, enhanced range and extended battery life for data networking applications such as Web surfing, instant messaging and e-mail.
The AR9285 is based on Atheros’ market-proven, single-chip 802.11 PCIe solutions that have shipped in tens of millions of PCs worldwide. Atheros’ integration expertise has enabled the industry’s most cost-effective, 2-layer half mini-card embedded module reference design. The single chip integrates the MAC/baseband and radio transceiver, as well as the power amplifier, low noise amplifiers and antenna switch – the entire RF front-end – providing a complete WLAN solution. In addition, the AR9285’s 8mm x 8mm QFN package provides size and cost benefits over larger, more expensive, BGA packages used by competitors. This solution supports Windows XP, Windows Vista, Mac OS and Linux operating systems.
Align for Home Networking: Atheros AR9002AP-1S
The Atheros Align AR9002AP-1S chipset for home networking targets a new generation of higher performance, value-priced wireless routing equipment, with increased capacity and range over legacy 802.11g. The solution is ideal for wireless AP/routers that support multiple users with robust operation of multiple data networking applications.
Featuring the industry’s highest level of integration for an 802.11n-based AP/router solution, the AR9002AP-1S chipset consists of the AR9285 1-stream MAC/BB/radio and the new Atheros AR7240 network processor System-on-Chip (SOC) which features advanced power management and a network processor with integrated 5-port Fast Ethernet switch – based on the company’s ETHOS technology. The AR7240 provides 400 MHz of processing power, ample to support 1-stream solutions as well as higher-performance, 2-stream, MIMO radio designs. The Atheros network processor is specifically engineered to optimize wireless performance by looking beyond clock speed and focusing on overall system efficiency. The AR7240 features a MIPS32 24K processor core, 64KB of instruction memory cache up to four times that offered by competitor NPUs, and a high speed 16-bit Double-Data-Rate (DDR) memory interface to dramatically increase raw memory speed. The AR7240 provides wirespeed NAT/routing performance for best-in-class Fast Ethernet routers. With its unmatched chip and board integration, the AR9002AP-1S delivers the lowest total bill of materials for a new generation of pricing and performance efficiency and value.
Align for Carrier Gateways, Consumer Electronics and PC Adapters: Atheros AR9271
The Atheros AR9271 single-chip USB solution provides enhanced Wi-Fi performance and value for home gateways, set-top boxes, gaming consoles, printers and a variety of other embedded wireless products. The solution can also be integrated into wireless USB adapters for notebooks and desktops, to enable simple, low-cost performance upgrades on legacy PCs.
The AR9271 WLAN USB single chip features a new architecture that integrates both a CPU and memory to run more of the wireless LAN function on-chip. Unlike competitive 11g and 11n USB solutions, the Atheros integrated CPU offloads the wireless processing overhead from the host appliance. This design breakthrough enables consumer electronics devices with host processors not originally intended to support wireless functions, to now offer robust Wi-Fi performance. With the AR9271’s innovative host offload capability, the WLAN operates autonomously and enables the main device application to operate seamlessly.
“With Atheros’ announcement of Align, two key factors immediately become evident,” said Craig Mathias, Principal at Farpoint Group. “The first is that we will shortly close the door on 802.11g as the primary WLAN technology – 802.11n-based solutions are going to dominate the market, and quickly, across all devices and applications. And the second is that Atheros continues to build on its position of leadership in wireless LAN components with a new direction that offers not only throughput of up to five times that of 11g, but is also very power- and cost-efficient.”
Range Enhancements
Atheros Align delivers more than double the coverage of legacy 11g products. Range is enhanced through the implementation of advanced 802.11n techniques including Space Time Block Coding (STBC) and Enhanced Receiver Synchronization (ERS), as well as all of the mandatory elements of the 1-stream specification. To further enhance network coverage, all Align solutions employ Signal Receive Combine (SRC), with optional support for 2 antennas.
“The Align portfolio of WLAN solutions represents the alignment of 1-stream, 11n-class performance with legacy 11g price points,” said Todd Antes, vice president of the wireless networking and computing business for Atheros. “With Align, consumers will benefit from a new class of standards-based Wi-Fi products that deliver greater networking efficiency on every key measure—performance, power and price.”
Lower Power Consumption
Leveraging a variety of power-saving techniques and protocols, the entire portfolio of Align solutions consume significantly less power than today’s leading 11g designs. Atheros has merged a linearized power amplifier (PA) with a low-noise amplifier (LNA) on chip to form a highly integrated RF front-end with built-in transmit and receive switch functionality. The company’s patented PA linearization scheme, Atheros’ Efficient Power Amplifier (EPA) Technology, delivers the power efficiencies of an external PA, while deriving the cost and manufacturing efficiencies of an integrated PA.
The company’s Wake-on-Wireless and Unscheduled Automatic Power Save Delivery (UAPSD) also contribute to the enhanced power efficiencies of Atheros’ 1-stream family. The AR7240 Wireless Router SOC delivers incremental power savings achieved with Atheros low-power, ETHOS Ethernet architecture, which dynamically detects the link status and cable length at a router’s port, and adjusts power usage accordingly.
EN-Genius Says…
It’s going to be some time before plain-vanilla 2.4 GHz 802.11g ceases to be the dominant species within the Wi-Fi ecosystem, but Atheros’ recently-introduced low-cost single-channel products may dramatically hasten the process. Although this non-MIMO 802.11n solution is not as fast as its more expensive multi-channel counterparts, it still retains most of the features and delivers more than twice data rate of today’s “g” silicon. By offering these capabilities at roughly the same price, the new Align series will help create a critical mass of higher-speed 802.11n laptops, media gateways, and other consumer equipment that will help solve the so-called first fax dilemma but still work with today’s 54 Mbit/s “g” routers. (Internet pioneer, Vint Cerf, once remarked that the Internet, like the Fax that came before it, was very difficult to sell at the outset because there was nobody to talk to until it became popular.)
The Align family uses a 2.4 GHz single-band radio that borrows much of the technology from Atheros’ dual-band XSPAN series but yields significant silicon and BOM costs. Offering a single-channel solution makes sense since it’s intended to displace the single-channel 802.11g radios currently powering the equipment being bought by the bulk of residential users. The radio/baseband/MAC used in all three devices has an integrated power amplifier (PA) which supplies +18 dBm to the antenna and boasts better power efficiency than previous products thanks to a new pre-distortion scheme in the output circuit, incorporating a feedback loop in the output chain that detects non-linearity and adjusts the modulation accordingly, Atheros says that it is able to achieve power efficiency that’s nearly equal to a discrete PA. While not available in their current XPAN MIMO products, Atheros says that it should appear in the next round of devices they roll out.
Also of note is that the Align AR9285 which is intended for laptop/desktop applications uses a PCI Express host interface instead of the older-style parallel PCI bus used by most previous products. This reflects the common adoption of the higher-performance PCIe interface in even value-priced computing products over the past year. For router/gateway applications, the AR9285 can be coupled to its companion AR7240 which features a 5-port 10/100 Ethernet switch and a MIPS32 host processor that handles packet routing tasks as well as most of the higher-layer parts of the 802.11 protocol stack.
The embedded version of the chip, the AR9271, features a USB 2.0 interface. Intended as a low-cost way to add high-speed Wi-Fi to a printer or other stand-alone box, it includes a RISC controller core that handles the higher-level MAC and management functions normally handled by the host. Offloading all but the simplest control tasks allows the host processor to run a very thin driver layer that does not place too much burden on a low-powered controller. As with all other Atheros products, the high levels of integration reduce BOM costs and give you a very compact PCB footprint.
When Atheros first started producing Wi-Fi silicon back in the late 1990s I was rightfully skeptical about the performance claims they made for their early chips. Over the years however, I’ve been pleased to watch their designs mature so that now I am relatively confident that, in most cases, their performance claims are somewhere in the ballpark of what they actually deliver. This is especially true for the baseband and MAC technology derived from their MIMO-capable XPAN series that powers the ALIGN family. Of course you should still read the fine print to make sure what those claims actually mean.
While Atheros is not wrong to claim that the new family can support traffic at up to 150 Mbit/s, it’s useful to understand that they demonstrated this speed under ideal conditions at short range (probably 5 - 10m with no walls in the way). As with any Wi-Fi stream, this translates into 75 - 100 Mbit/s worth of useable data when you take away the bandwidth soaked up by protocol overhead. When I asked how the chips performed under more realistic conditions, Atheros said that they have seen their products consistently deliver 30 Mbit/s worth of useable data from a 20 MHz Wi-Fi channel across 50 ft – a distance that they feel will allow them to cover in a so-called typical suburban home of about 2400 square feet. Apparently, they’ve conducted quite a bit of performance testing in real houses: including one in Silicon Valley they bought specifically to use as a test site. Atheros also says that when the Align devices are run in the optional HT40 mode allowing a 40 MHz channel they can deliver 40 Mbit/s under the same conditions.
 The AR9002AP-1S chipset for AP/Routers and AR9285 single chip for PCs are sampling now. The AR9271 embedded USB solution will begin sampling in late Q4 2008. Atheros is keeping pricing closely guarded, but says that pricing the their Align series will be “very competitive with existing 802.11g solutions.”
Product Page
|
|
|
|
|
