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Broadcom comes third to next gen WiFi – less urgency all round

The first thing you learn as a journalist is that when a company says it has done something for first, it is likely that it is the “last” company to go down that route, so we have to “check” where it is in the pecking order and make that clear.

So when Broadcom said this week that it was the First company to have a complete ecosystem of 802.11ax solutions, we went back through archives asking when it had announced it first devices and who else had them.

The 802.11ax standard has been delayed and confounded by vote cheats, companies who illegally agree among themselves techniques for an IEEE committee to approve, who then crowd-vote it into the standard. The chairman revealed in the 802.11ax proceedings that no less than 18 separate firms, created the DensiFi SIG (Special Interest Group) to hijack the next generation WiFi standard. Naturally it took months to uncover the plot, and to change the voting system to dilute its effect, and all those companies achieved was to slow the standard so that silicon is here, and in May the first WLAN Test Toolkit for 802.11ax was launched, but the completed standard may not be with us for another year.

The DensiFi cartel had Intel, LGE, Broadcom, Marvell, MediaTek, Qualcomm, Huawei, Orange, NTT, NTT DoCoMo, Samsung, ZTE, Apple, Cisco, Sony, Toshiba, Newracom, and Quantenna as members, and they all walked away from it last year, over the risk of losing their votes and having smaller companies take control of the standard. It was not widely publicized, but among the community it was widely known. Let’s face it, those companies have the market weight to force a standard anyway, and we’re not sure how they all managed to agree, or why they tried to bypass the IEEE. No legal action was taken.

802.11ax is next gen WiFi, designed to cope with top speeds of 10 Gbps using both 2.4 and 5 GHz spectrum (real world top speeds will be closer to 4.8 Gbps), MIMO and both 4 stream downlink and uplink MU-MIMO, simultaneous transmit/receive (STR) and is based on OFDMA signaling and 1024 QAM modulation. The OFDMA is what allows it to move up one QAM modulation, but the extra capacity is achieved by counting in multiple bands, and having both ends speak at the same time (STR) and letting devices speak to an Access Point using MU-MIMO – it was only possible one way – downstream- in 802.11ac. The blurb says it is 4 times faster than AC, but we know how little this can mean to overall throughput improvement – after all, it’s still WiFi.

The first company to publicly launch into 802.11ax chip hardware was Quantenna last October with samples in the first quarter 2017, Qualcomm Atheros followed in February with samples around now; Broadcom is only announcing its silicon now. It’s one of those announcements were first means third. And that’s just in the US, although Taiwanese, Chinese and Korean companies have done demonstrations of some of the technologies, they have not actually announced a chip for sampling.

Broadcom this week announced what it calls Max WiFi, a family of chips around 802.11ax. It claims four times faster download, six times faster upload, four times better coverage, and seven times better battery life some of which will be true, but that’s the standard working there really, not Broadcom.

While the US sails past 12 devices per home today, and a likely 15 devices in the near future, Broadcom asks us to believe that a typical family of four are expected to have an average of 50 connected devices by 2022. Surely most of the IoT devices will talk over Zigbee or Z-Wave to a hub, which will talk over WiFi to a router, so they don’t really count, although we suspect that Broadcom is counting them. It hypes VR as a data type that will eat progressively more data.

The chips include the BCM43684 for home routers, the 43694 for enterprise routers and 4375 for smartphones with just 2 antennas supported, which is the current state of the art.

There are improvements with switching off WiFi when it is not being used and rapid wake up times; something called spatial reuse which lets access points share channel capacity – effectively this sounds like mesh style inter AP communication – telling each other about empty channels. That’s why it has a zero wait DFS – as LAA emerges in the US, more and more devices will need to rely on jumping out of WiFi channels which sense interference, to one where there is none and dynamic frequency selection will be used far more often. The release was accompanied by a whole string of equipment vendors singing the praises of both Broadcom and the 802.11ax technology including Altice, Arris, Aerohive, ASUS, D-Link, Microsoft, Netgear, Sagemcom and Technicolor.

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