We’ve devoted a lot of blog ink recently to forward looking AR/VR applications. The mobile short-range wireless performance needed for these apps has spurred the technology industry’s hunger for a new connectivity option that excels where Bluetooth/BLE and Wi-Fi don’t. UWB answers this need head on, delivering the high data throughput, ultra-low latency and ultra-low power consumption needed for tomorrow’s smart glasses and wearables.
But in order to architect the AR/VR connected devices of tomorrow, we must first solve the connectivity needs of wireless devices today. And for traditional gaming and audio apps, it’s clearer than ever that collectively we’re reaching the outer limits of what’s possible with legacy short-range connectivity platforms. The time for UWB is right now.
Gaming mice provide a prime example.
Gaming device OEMs are continuously pushing performance boundaries as they compete – aggressively! – to provide gamers with ultra-fast and ultra-light mice with finely balanced ergonomic and power profiles. Wired mice have traditionally dominated the high-performance mouse market due to the latency advantages they provide, but this trend is changing with the latest generation of wireless gaming mice. Premium wireless mice aspire to deliver wired-like performance and latency without the wires to ensure fast, fluid gameplay and motion without the weight or tangle of cords and cables.
Premium wireless gaming mice today are typically equipped with proprietary 2.4 GHz wireless connectivity, sometimes with a Bluetooth option for convenience. Why 2.4 GHz narrow band spectrum? Because it was the only viable option at the time these mice were conceived and designed.
Proprietary 2.4 GHz connectivity comes with its own challenges (more on that in a moment), but it’s typically much lower latency than Bluetooth, and specialized wireless gaming mice leverage this advantage to achieve faster polling rates and lower latency.
WHY POLLING RATES AND LATENCY ARE IMPORTANT
Polling rate is the speed at which a mouse sensor communicates its position/location input to a computer per second, which is essential for the accurate tracking of movement. The more samples you take, the closer you are to recording the actual movements of the mouse.
A mouse with a polling rate of 1,000 Hz inputs 1,000 times per second (once per millisecond), and this happens to be a pretty common spec among mainstream gaming mice. Innovative mouse vendors are tweaking 2.4 GHz implementations to push polling rates to new heights – peaks as high as 4,000 Hz – to deliver improved precision and speed for better overall gaming performance.
But a faster polling rate is not enough on its own to boost gaming performance. Latency is key for responsiveness. You could accurately record the mouse movement at 4,000 Hz, but if the lag to convey that information to the PC is too long, it’s hard for the gamer to benefit from the resolution 4,000 Hz gives them. The gamer would show a tendency to keep moving the mouse beyond the desired position until the action on the screen catches up. The more the latency lag, the more the overshoot.
Faster mouse inputs and lower latency enable improved responsiveness, and serious gamers play close attention to these specs because they can enhance their competitive edge. 4,000 Hz polling is an impressive benchmark and SPARK applauds the innovation that made it possible! But unfortunately, 2.4 GHz comes with some inherent penalties.
Among the more pressing issues, 2.4 GHz narrow band spectrum services Bluetooth/BLE, Wi-Fi and ZigBee. It’s a congested frequency band that at any given moment could be occupied by myriad devices in a gamer’s immediate vicinity, all vying for spectrum. This can create interference problems, and onboard USB dongles can create additional noise as well – all of which can negatively impact latency and overall gaming performance.
4,000 Hz polling over 2.4 GHz is also very likely the end of the road in terms of achievable gaming mouse performance using legacy wireless platforms. There’s simply no discernible path to achieving 8,000 Hz polling rates – the next major milestone on the industry’s development roadmap – with 2.4 GHz or Bluetooth-based gaming mice.
A NEW PERFORMANCE STANDARD
With SPARK UWB, 4,000 Hz polling rate is where things start.
We consider it the baseline for achieving premium gaming mouse performance going forward – with no special optimizations needed to contend with interference like you’d need at 2.4 GHz. And with SPARK UWB, 4,000 Hz polling isn’t qualified in terms of peak performance – 4,000 Hz is the sustained performance.
Moreover, SPARK UWB performance allows a clear roadmap to achieving 8,000 Hz performance – so the innovation doesn’t stop at 4,000 Hz.
SPARK Microsystems’ UWB technology delivers high data rate for high resolution 4,000 Hz polling and low latency data transfer that is as good as, or better than the polling rate. In the case of 4,000 Hz, with SPARK UWB samples are taken every 0.25 ms and the data is transferred over the wireless link to the PC within 0.25 ms or better (this includes button presses). 2.4 GHz can in some cases transfer the amount of data 4,000 Hz polling requires, but it may take more than 15 ms to get the data to the PC with 2.4 GHz technologies like Bluetooth.
UWB’s wide frequency range ensures that it’s far less congested than 2.4 GHz narrow band spectrum, allowing for multiple channels and ample flexibility to spectrum hop as needed. And the underlying impulse radio technology means that UWB is less impacted by multipath phase distortion issues and can filter out unwanted interferers, making it more robust for greater concurrency. SPARK UWB can enable multiple gamers to play together at close range at 4,000 Hz polling rate, and provide automatic fallback modes for more players.
As an added benefit – and it’s a pretty significant benefit in its own right – SPARK UWB’s ultra-low power profile makes it possible to use smaller batteries within wireless gaming mice without sacrificing uptime between charges. This makes for a sleeker mouse design, and crucially, this also helps reduce the weight of the mouse for faster gameplay and even better performance.
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Traditional gaming and multimedia apps will one day be subsumed within the broader AR/VR technology ecosystem, and the SPARK team has our eyes on the future as we innovate the BAN/PAN connectivity needed to enable exceptional mobile AR/VR experiences.
Wireless gaming mice exemplify the limitations of legacy short-range wireless connectivity today, but the door is open to a new generation of UWB-based gaming mice for tomorrow’s hardcore gamers on the path to full AR/VR immersion.