Qualcomm unveils pre-standard 802.11ax silicon

There is a pattern in the advanced WiFi chip industry, in which start-up Quantenna makes an early move towards a new standard, and Qualcomm follows hard on its heels. In October, Quantenna unveiled the first access point platform to support the upcoming 802.11ax standard, which will sample to early access partners during this quarter. Now Qualcomm says it has gone one better with an end-to-end 11ax offering.

The latest WiFi standard will not be finalized until later this year so these early products are based on draft 1.0 of the IEEE specifications. This is common practice in the WiFi industry, with some chipmakers wanting to be ready to pounce as soon as the market starts to become real – which usually means having a pre-standard offering that can be tweaked later to bring it in line with any changes to the specs.

The 802.11ax spec is particularly geared to high density, high throughput environments such as stadiums or large apartment blocks, boosting data rates and allowing more simultaneous clients to be supported. It is primarily for indoor use – outdoor operation will be limited to stationary and pedestrian speeds.

While most WiFi standards focus on the data capacity of a whole network shared by multiple users, 11ax will address and boost the actual data rate to each individual device. The IEEE is looking to increase that speed at least fourfold compared to current 802.11ac. Other 11ax objectives are to maintain or improve power efficiency and maintain backward compatibility and coexistence.

Qualcomm’s offering includes the IPQ8074 system-on-chip (SoC) for access points and QCA6290 chip for client devices. It says the technology will deliver up to four times greater capacity, and four times faster user throughput, together with longer battery life for devices.

Qualcomm Technologies expects to sample the IPQ8074 and QCA6290 during the first half of 2017.

Its 802.11ax solutions support 12 streams (eight in the 5 GHz band and four in 2.4 GHz); 8×8 Multiuser-MIMO; and 80 MHz channels. The 4x improvement Qualcomm is claiming was achieved using a 12×12 configuration, with MU-MIMO on uplink and downlink, and eight 80 MHz streams. This enabled the IPQ8074 to deliver up to 4.8Gbps over larger coverage areas than current WiFi standards.

The chips also incorporate OFDMA and traffic scheduling to boost efficiency and user throughput further, and enable a more consistent performance. Qualcomm says this approach to resource allocation, along with the optimization of wake-up time, can reduce WiFi power consumption by two-thirds at the same performance.

The speed and battery life benefits will be greatest for 11ax-based devices, but older 802.11ac and 802.11n technologies will also gain some improvements when connected to 11ax networks.

“Capacity – not peak speed – has become the most important measure of a network’s ability to handle the ever-increasing demands of today’s diverse mix of application and services,” said Rahul Patel, general manager of connectivity at Qualcomm Technologies. He pointed to other capacity-focused technologies the company is pushing to expand WiFi’s performance and use cases, such as MU-MIMO, WiFi SON (self-optimizing network) and 802.11ad.

David Henry, SVP of home networking at WiFi equipment vendor Netgear, supported the Qualcomm press release, saying: “802.11ax is not an incremental upgrade to keep pace with today’s demands. The technology will reset the bar for what matters most in networking, and will lay the foundation of network capacity for years to come.”

The IPQ8074 also features Qualcomm’s WiFi SON. It integrates an 11ax radio, MAC and baseband, plus a quad-core 64-bit A53 CPU and dual-core network accelerator to provide an offloaded 11ax subsystem.

The QCA6290 is an 802.11ax client device SoC which supports 2×2 MU-MIMO and can realize the benefits of 8×8 MU-MIMO by supporting the 8×8 sounding mechanism. It can achieve up to 1.8 Gbps peak speeds using Dual Band Simultaneous (DBS) combining 2.4 GHz and 5 GHz bands, and higher order modulation (1024QAM).

Meanwhile, Quantenna’s first 11ax offering, the QSR10G-AX, is based on its QSR10G Wave 3 WiFi access point platform, a design which includes a Cavium chipset. This will support 12 streams, 8×8 in 5 GHz and 4×4 in 2.4 GHz. It will support downlink and uplink OFDMA to improve network efficiency in dense environments as well as higher uplink rates; and to support more devices at once by dedicating different sub-carriers for individual clients. The firm added a second product, the QSR5G-AX, with support for dual-band, dual concurrent 4×4 + 4×4 operation, in January.

Huawei has been leading the 11ax standards effort and back in 2014 it demonstrated some of the technologies which it has submitted to that process, as part of its Smart Stadium solution.  Included in its technology mix were MIMO-OFDA, dynamic spectrum allocation, interference coordination and hybrid access techniques. The company said this combination, and 11ax in general, will “break the logjam of classical WiFi wideband radio and baseband processing to increase user data rates”.

MIMO-OFDA combines large MIMO arrays with OFDM schemes, which divide sub-carriers into separate data streams, and send them out at right angles to one another, aiming to find a pathway with least interference in a congested zone. OFDA is based on existing OFDM schemes, but adds a multiple access component, so that subsets are assigned within the subcarrier frequencies to create a bigger pipe for each individual device.