Showing posts with label Active noise control (ANC). Show all posts
Showing posts with label Active noise control (ANC). Show all posts

Monday, November 10, 2014

Building (sound) character into cars

Tina Jeffrey
Modern engines are overachievers when it comes to fuel efficiency — but they often score a C minus in the sound department. Introducing a solution that can make a subtle but effective difference.

Car engines don’t sound like they used to. Correction: They don’t sound as good as they used to. And for that, you can blame modern fuel-saving techniques, such as the practice of deactivating cylinders when engine load is light. Still, if you’re an automaker, delivering an optimal engine sound is critical to ensuring a satisfying user experience. To address this need, we’ve released QNX Acoustics for Engine Sound Enhancement (ESE), a complementary technology to our solution for active noise control.

The why
We first demonstrated our ESE technology at 2014 CES
in the QNX technology concept car for acoustics.
Many people assume, erroneously, that ESE is about giving cars an outsized sonic personality — such as making a Smart ForTwo snarl like an SRT Hellcat. While that is certainly possible, most automakers will use ESE to augment engine sounds in subtle but effective ways that bolster the emotional connection between car and driver — just like engine sounds did in the past. It boils down to creating a compelling acoustic experience for drivers and passengers alike.

ESE isn’t new. Traditionally, automakers have used mechanical solutions that modify the design of the exhaust system or intake pipes to differentiate the sound of their vehicles. Today, automakers are shifting to software-based ESE, which costs less and does a better job at augmenting engine sounds that have been degraded by new, efficient engine designs. With QNX Acoustics for Engine Sound Enhancement, automakers can accurately preserve an existing engine sound for use in a new model, craft a unique sound to market a new brand, or offer distinct sounds associated with different transmission modes, such as sport or economy.

The how
QNX Acoustics for Engine Sound Enhancement is entirely software based. It comprises a runtime library that augments naturally transmitted engine sounds as well as a design tool that provides several advanced features for defining and tuning engine-sound profiles. The library runs on the infotainment system or on the audio system DSP and plays synthesized sound synchronized to the engine’s real-time data: RPM, speed, throttle position, transmission mode, etc.




The ESE designer tool enables sound designers to create, refashion, and audition sounds directly on their desktops by graphically defining the mapping between a synthesized engine-sound profile and real-time engine parameters. The tool supports both granular and additive synthesis, along with a variety of digital signal processing techniques to configure the audio path, including gain, filter, and static equalization control.



The value
QNX Acoustics for Engine Sound Enhancement offers automakers numerous benefits in the design of sound experiences that best reflect their brand:

  • Ability to design consistent powertrain sounds across the full engine operating range
     
  • Small footprint runtime library that can be ported to virtually any DSP or CPU running Linux or the QNX OS, making it easy to customize all vehicle models and to leverage work done in existing models
     
  • Tight integration with other QNX acoustics middleware libraries, including QNX Acoustics for Active Noise Control, enabling automakers to holistically shape their interior vehicle soundscape
     
  • Dedicated acoustic engineers that can support development and pre-production activities, including porting to customer-specific hardware, system audio path verification, and platform and vehicle acoustic tuning
     
If you’re with an automaker or Tier One and would like to discuss how QNX Acoustics for ESE can address your project requirements, I invite you to contact us at anc@qnx.com.

In the meantime, learn more about this solution on the QNX website.

Monday, August 18, 2014

QNX Acoustics for Active Noise Control wins a Silver Stevie

Lynn Gayowski
Lynn Gayowski

The winners of the 11th annual International Business Awards have been announced and I'm happy to share that QNX Acoustics for Active Noise Control (ANC) has won a Silver Stevie Award in the software category, for Best New Product or Service of the Year! The awards program honours the achievements of organizations and working professionals worldwide, and received more than 3,500 nominations this year from dozens of countries. It feels great to be chosen as a winner among so many entries.
If you're unfamiliar with QNX Acoustics for ANC, it's a software solution that can dramatically reduce unwanted engine harmonic noise inside the cabin of a vehicle. The software's algorithms for noise cancellation can run on an existing CPU or DSP in the infotainment system, eliminating the need for dedicated hardware controller modules. The end result is significant savings for automakers and a quieter ride for drivers and passengers.
This is the second award for QNX Acoustics for ANC, after a win in February at the Embedded World conference's embedded AWARDs. If you want to learn more about the solution, read our white paper titled A Software-Based Approach to Active Noise Control in Automobiles. Congratulations QNX!

Thursday, August 7, 2014

Acoustics, ADAS, and autonomous cars, oh my!

Lynn Gayowski
Lynn Gayowski
Trying to make sense of where automotive technology is headed can be as tricky as finding your way through a poppy field while avoiding flying monkeys. Well strap on your shiny, red, video-watching shoes because Derek Kuhn can help. Derek, VP marketing and sales for QNX, was interviewed at Telematics Detroit and did an excellent job of summing up the latest on automotive acoustics, advanced driver assistance systems (ADAS), and autonomous cars.

QNX announced the new QNX OS for Automotive Safety at Telematics Detroit, so safety was clearly top of mind during the interview. One question posed was whether automakers have the potential to use safety options as revenue generators. There's a quote here I love: "Safety shouldn't be about premium." OEMs need to find cost-effective ways to bring next-generation safety to the mass market, not just luxury vehicles.

The section of the video I find most interesting is when Derek discusses how acoustics in a car play a big role in creating "the emotion and experience of driving." Noise reduction technology and engine sound enhancement both have a significant impact on a driver's affinity for a vehicle, and OEMs are taking note.

Check out the video for yourself here, my pretties:



Monday, June 23, 2014

Just add jelly

I like toast. I also like peanut butter. But you know what I really like? The two of them together. Not only does the combination taste great, but making it is easy: all I need is a knife, a toaster, and a plate. Heck, sometimes, I even skip the plate!

Why am I mentioning this? Well, when designing an embedded system, you often need to source third-party hardware or software components. And when doing so, you should always make sure they follow the toast-and-peanut-butter rule: work together out of the box, with little or no fuss. That way, you can focus on adding your own special jelly and transform your peanut-butter toast into a one-of-a-kind PB&J that customers can't get enough of. (Man, I should never write when I'm hungry!)

Evan-Amos, Wikimedia Commons
Seriously, there is no better way to jump-start an embedded project than to choose components that already work in concert. Which is the idea behind today's announcement between Cadence and QNX Software Systems. In a nutshell, they have announced that QNX Acoustics for Active Noise Control (ANC) has been ported to the Cadence Tensilica HiFi Audio/Voice DSP core.

If you're unfamiliar with QNX Acoustics for ANC, it's a software solution for reducing unwanted engine "boom" inside passenger vehicles. Compact and efficient, it can run on a processor or DSP core in the vehicle's infotainment system or audio amplifier, eliminating the dedicated hardware of conventional ANC solutions.

According to Peter McCarthy of QNX, “modern fuel-saving techniques, such as deactivating cylinders when engine load is light, can cause irritating boom noise that distracts the driver. QNX Acoustics for ANC generates targeted anti-noise over the car’s audio system to cancel out this boom for a more enjoyable ride. By combining QNX Acoustics for ANC with the widely deployed Cadence Tensilica HiFi Audio/Voice DSP core, system designers can reduce engine noise while also eliminating the costs associated with designing and prototyping a custom hardware controller module.”

For more information, read the press release and check out previous posts on QNX Acoustics for ANC.


Wednesday, May 14, 2014

Using a smaller BOM to make less boom

Don't know about you, but where I live, the price of gas has rocketed through the troposphere and is fast approaching the upper stratosphere. Which is to say, it has gone through the proverbial roof. It was almost $1.40 a liter (over $5 a gallon) the last time I stopped at a pump and is set to climb even higher, now that summer is approaching.

Small wonder that, for many car buyers, fuel economy is top of mind. Automakers are wise to this and have adopted a variety of measures to make their cars sip gas more slowly. For instance, many cars now deactivate cylinders when engine load is light and use fewer sound-damping materials to shed weight — because schlepping fewer pounds means less work, and less work means less gas.

These techniques save gas all right, but at a price: increased engine “boom” noise that can both annoy and fatigue the driver — not to mention everyone else in the vehicle. That's a problem. To address it, automakers use active noise control, or ANC, which plays noise-cancelling signals over speakers in the vehicle cabin. All fine and good, but until now, ANC solutions have used dedicated hardware, which can drive up Bill of Materials (BOM) costs and make it difficult to leverage the latest ANC technologies.

What to do? That's the subject of a recent whitepaper by my inestimable colleague Tina Jeffrey. Tina outlines some design considerations for ANC systems (choosing the right microphones makes a difference, for example) but mostly, she focuses on the advantages of running ANC logic on the processor or DSP of the car's infotainment system — as opposed to on a dedicated ANC module.

The benefits are many, including lower BOM costs, greater design flexibility, better cooperation between various acoustic functions in the car and — here's the one I like — less boom. But why sit there listening to me drone on about this? Download Tina's paper now and get the real deal.




Software-based ANC: a smaller BOM, with less boom.

Tuesday, February 25, 2014

QNX drives home (quietly) with embedded award

Every year, the organizers of the Embedded World conference hold the embedded AWARDs to recognize the most innovative software, hardware, and tools for embedded developers. And this year, they selected QNX Acoustics for Active Noise Control, the new QNX solution for eliminating engine "boom" noise in cars, as the winner in the software category.

This marks the third time that QNX Software Systems has taken home an embedded AWARD. The company also won in 2004 for power management technology and in 2006 for its multicore tools and OS — and in 2010, it nabbed a finalist spot for its persistent publish/subscribe messaging. That's a lot of plaques.

QNX Acoustics for ANC eliminates the need
for costly dedicated ANC hardware.
So why did QNX Acoustics for ANC get the blue ribbon treatment? I can't speak on behalf of the Embedded World judges, but check out this overview I wrote a few months ago. Or better yet, read this deeper dive from my colleague Tina Jeffrey.

Or skip the middle man entirely and check out the product page, which does a nice job of summarizing what QNX Acoustics for ANC is all about.

Wednesday, February 5, 2014

My top 10 QNX Auto posts from 2013

Normally, people write this kind of post at the beginning or end of a calendar year. But as an old friend once said, “Paul defines his own kind of normal.” He may have been right, I don’t know. What I do know is that this is definitely a personal list. It consists of posts that either made me laugh, taught me something I didn’t know, or helped me see things in a new light. I hope they do the same for you.

Disclosure: I wrote a couple of the posts in question. Because, sometimes, the best way to learn about something or see it in a new light is to write about it. :-)

Okay, enough preliminaries, let’s get to it…

  • What happens when autonomous becomes ubiquitous? — One question, seventeen answers.
     
  • Top 10 lessons learned from more than a decade in automotive — When it comes to software in the car, John Wall is the man.
     
  • Protecting software components in an ISO 26262 system — Sometimes, software components can be downright delinquent.
     
  • Why doesn’t my navigation system understand me? — Big data might be important, but small data can add a personal touch.
     
  • Top 10 challenges facing the ADAS industry — For ADAS systems to be successful, a safety culture must be embedded in every organization in the supply chain. And that’s just the first challenge.
     
  • Reducing driver distraction with ICTs — Yes, mobile phones can contribute to driver distraction. But they can also help solve the problem.
     
  • A sound approach to creating a quieter ride — Paradoxically, the best way to eliminate engine noise is to generate noise.
     
  • What's the word on HTML5? — If you want to know what experts at Audi, OnStar, Gartner, Pandora, TCS, and QNX think about HTML5 in the car, this is the post with the most (videos, that is).
     
  • A matter of context — A look at how digital instrument clusters can help provide the right information, at the right time.
     
  • My top moments of 2013 — Because this reminds me of the fantastic momentum QNX is building in automotive.
     
  • HTML5 blooper reel — Because laughter.

Oops, I guess that makes 11.

Thursday, January 30, 2014

QNX acoustics technology shortlisted for 2014 embedded AWARD

Okay, first things first. I didn't get the capitalization wrong. The name of the award really is spelled that way. I thought it odd at first, but I'm getting used to it. And besides, who am I to complain? After all, I spend a good part of my life promoting a product whose name is spelled all uppercase, and... where was I? Oh yes, the award!

Every year, the folks who organize the embedded world Exhibition&Conference hold the embedded AWARDs, which honor the most innovative software, hardware, and tools for embedded developers. And this year, the competition judges selected QNX Acoustics for Active Noise Control as a finalist in the software category.

If you aren’t familiar with our ANC solution, allow me to provide an overview — which will also help explain why the embedded AWARD judges are so impressed.

Automakers need to reduce fuel consumption. And to do that, they employ techniques such as variable engine displacement and operating the engine at lower RPM. These techniques may save gas, but they also result in "boom" noise that permeates the car's interior and can lead to driver distraction. And who needs more distraction?

QNX Acoustics for Active Noise Control can integrate 
seamlessly into a vehicle's infotainment system.
To reduce this noise, automakers use ANC, which plays “anti-noise” (sound proportional but inverted to the offending engine tones) over the car's speakers. The problem is, existing ANC systems require dedicated hardware, which adds design complexity, not to mention significant Bill of Materials costs. And who needs more costs?

Enter QNX Acoustics for ANC. Rather than use dedicated hardware, QNX ANC provides a software library that can run on the existing DSP or CPU of the car's head unit or audio system. This approach not only reduces hardware costs, also enables better performance, faster development, and more design flexibility. I could go on, but I will let my colleague Tina Jeffrey provide the full skinny.

Did I mention? This wouldn’t be the first time QNX Software Systems is tapped for an embedded AWARD. It has won two so far, in 2006 and 2004, for innovations in multi-core and power-management technology. It was also a finalist in 2010, for its persistent publish/subscribe messaging. Here's to making it a hat trick.

Friday, January 10, 2014

QNX at CES: The media’s take

No, CES isn’t over yet. But the technology concept cars showcased in the QNX booth have already stoked the interest of journalists attending the event — and even of some not attending the event. So here, in no particular order, are examples of what they're saying.

Oh, and I’ve added a couple of stories that aren’t strictly CES-related, but appeared this week. They were too relevant to pass up.

That's it for now. I aim to post more stories and videos early next week. Stay tuned.

Tuesday, January 7, 2014

The QNX sound machine at CES

If you’ve ever had the pleasure of attending the Consumer Electronics Show, you’ll know that it’s a crowded place full of lights and noise. In the automotive North Hall, much of the cacophony comes from the legions of car customizers blasting bass from sedan-sized speakers. This year, QNX has brought a new kind of technology concept car to CES, based on a Kia Soul, that offers some subtler forms of sound artistry. (Sorry, hamster fans—I don’t think we’ll have your favorite mascot in the QNX booth.)


A sound ride: the new QNX technology concept car for acoustics

Let’s start with noise. Everyone likes a booming radio, sometimes. But if that’s the only tool you have to drown out engine noise you’ll go deaf. That’s where Active Noise Control (ANC) comes in. Think of ANC as a more sophisticated version of noise cancelling headphones that you don’t need to wear. Not only does ANC help keep the car’s cabin quiet, but the QNX solution is software based and doesn’t require a dedicated hardware module, saving the OEM and the consumer money.

The best part about ANC is that it helps cars become more fuel efficient. Huh? To keep car interiors quiet, automakers add baffling in the doors and under the floor to help mute engine noise. Dragging around that extra weight costs fuel. So removing the ballast (I mean baffles) lets the automakers make more fuel-efficient cars. And with ANC, which helps eliminate the extra noise caused by this approach, everyone wins.

Beyond wideband
Next up: a new level of call quality. If you’ve had the pleasure of conversing between two newer smartphones (BlackBerry Z10 or Z30, iPhone 5, Nokia Lumina 520, Samsung Galaxy S4, ...) you may have noticed that the call sounded better than what you’re used to. That’s because many newer phones support something called wideband audio (or HD Voice), which transmits more audible frequencies to make the call sound clearer. That’s good, but QNX wants to show what’s possible beyond wideband. So in the QNX technology concept car for acoustics, we’re demoing a new audio feature called full-band stereo calling, which is like having phone calls with CD quality audio. A full-band call has over six times the transmitted frequency range of a standard call, and more than double that of wideband. And as the name suggests, full-band stereo provides two independent channels, adding to the depth and sense of presence, making the call quality something that just has to be experienced.

Sound like a V8, sip like a Volt
Lastly — we get to pump up the volume! The technology concept car for acoustics also sports engine sound enhancement (ESE), which plays synthesized engine sounds over speakers inside the car. With ESE, your engine appears to sound a little more throaty. It may not be obvious, but this is also a fuel saving technology! As carmakers look for creative ways to turn gasoline slurpers into sippers, they’re implementing technologies that dynamically modify engine cylinder firing. Those changes can sometimes make a perfectly powerful engine sound anemic, which negatively impacts customer first impressions. Unfortunately, most people want a car that sounds and performs like it has a huge V8 even if they expect it to sip gas like a Chevy Volt. Both ANC and ESE can help the customer get over their performance anxiety. ESE also lets drivers get in tune with their engine, making it easier to shift by ear.

If you’re up for a little fun, you can also use ESE to make your car sound like something completely different. We’re playing the ESE audio outside the car as well as inside it. The Kia is using QNX ESE audio to masquerade as another car. Tweet us at @QNX_Auto if you can guess what it is!


Wednesday, October 30, 2013

My top moments of 2013 — so far

Paul Leroux
Yes, I know, 2013 isn’t over yet. But it’s been such a milestone year for our automotive business that I can’t wait another two months to talk about it. And besides, you’ll be busy as an elf at the end of December, visiting family and friends, skiing the Rockies, or buying exercise equipment to compensate for all those holiday carbs. Which means if I wait, you’ll never get to read this. So let’s get started.


We unveil a totally new (and totally cool) technology concept car
Times Square. We were there.
It all began at 2013 CES, when we took the wraps off the latest QNX technology concept car — a one-of-a-kind Bentley Continental GT. The QNX concept team outfitted the Bentley with an array of technologies, including a high-definition DLP display, a 3D rear-view camera, cloud-based voice recognition, smartphone connectivity, and… oh heck, just read the blog post to get the full skinny.

Even if you weren’t at CES, you could still see the car in action. Brian Cooley of CNET, Michael Guillory of Texas Instruments, the folks at Elektrobit, and Discovery Canada’s Daily Planet were just some of the individuals and organizations who posted videos. You could also connect to the car through a nifty web app. Heck, you could even see the Bentley’s dash on the big screen in Times Square, thanks to the promotional efforts of Elektrobit, who also created the 3D navigation software for the concept car.

We ship the platform
We wanted to drive into CES with all cylinders firing, so we also released version 2.0 of the QNX CAR Platform for Infotainment. In fact, several customers in the U.S., Germany, Japan, and China had already started to use the platform, through participation in an early access program. Which brings me to the next milestone...

Delphi boards the platform
The first of many.
Also at CES, Delphi, a global automotive supplier and long-time QNX customer, announced that version 2.0 of the QNX CAR Platform will form the basis of its next-generation infotainment systems. As it turned out, this was just one of several QNX CAR customer announcements in 2013 — but I’m getting ahead of myself.

We have the good fortune to be featured in Fortune
Fast forward to April, when Fortune magazine took a look at how QNX Software Systems evolved from its roots in the early 1980s to become a major automotive player. Bad news: you need a subscription to read the article on the Fortune website. Good news: you can read the same article for free on CNN Money. ;-)

A music platform sets the tone for our platform
In April, 7digital, a digital music provider, announced that it will integrate its 23+ million track catalogue with the QNX CAR Platform. It didn't take long for several other partners to announce their platform support. These include Renesas (R-Car system-on-chip for high-performance infotainment), AutoNavi (mobile navigation technology for the Chinese market), Kotei (navigation engine for the Japanese market), and Digia (Qt application framework).

We stay focused on distraction
Back in early 2011, Scott Pennock of QNX was selected to chair an ITU-T focus group on driver distraction. The group’s objective was serious and its work was complex, but its ultimate goal was simple: to help reduce collisions. This year, the group wrapped up its work and published several reports — but really, this is only the beginning of QNX and ITU-T efforts in this area.

We help develop a new standard
Goodbye fragmentation; hello
standard APIs.
Industry fragmentation sucks. It means everyone is busy reinventing the wheel when they could be inventing something new instead. So I was delighted to see my colleague Andy Gryc become co-chair of the W3C Automotive and Web Platform Business Group, which has the mandate to accelerate the adoption of web technologies in the car. Currently, the group is working to draft a standard set of JavaScript APIs for accessing vehicle data information. Fragmentation, thy days are numbered.

We launch an auto safety program
A two-handed approach to
helping ADAS developers.
On the one hand, we have a 30-year history in safety-critical systems and proven competency in safety certifications. On the other hand, we have deep experience in automotive software design. So why not join both hands together and allow auto companies to leverage our full expertise when they are building digital instrument clusters, advanced driver assistance systems (ADAS), and other in-car systems with safety requirements?

That’s the question we asked ourselves, and the answer was the new QNX Automotive Safety Program for ISO 26262. The program quickly drew support from several industry players, including Elektrobit, Freescale, NVIDIA, and Texas Instruments.

We jive up the Jeep
A tasty mix of HTML5 & Android
apps, served on a Qt interface,
with OpenGL ES on the side.
If you don’t already know, we use a Jeep Wrangler as our reference vehicle — basically, a demo vehicle outfitted with a stock version of the QNX CAR Platform. This summer, we got to trick out the Jeep with a new, upcoming version of the platform, which adds support for Android apps and for user interfaces based on the Qt 5 framework.

Did I mention? The platform runs Android apps in a separate application container, much like it handles HTML5 apps. This sandboxed approach keeps the app environment cleanly partitioned from the UI, protecting both the UI and the overall system from unpredictable web content. Good, that.

The commonwealth’s leader honors our leader
I only ate one piece. Honest.
Okay, this one has nothing to do with automotive, but I couldn’t resist. Dan Dodge, our CEO and co-founder, received a Queen Elizabeth II Diamond Jubilee Medal in recognition of his many achievements and contributions to Canadian society. To celebrate, we gave Dan a surprise party, complete with the obligatory cake. (In case you’re wondering, the cake was yummy. But any rumors suggesting that I went back for a second, third, and fourth piece are total fabrications. Honestly, the stories people cook up.)

Mind you, Dan wasn’t the only one to garner praise. Sheridan Ethier, the manager of the QNX CAR development team, was also honored — not by the queen, but by the Ottawa Business Journal for his technical achievements, business leadership, and community involvement.

Chevy MyLink drives home with first prize — twice
There's nothing better than going home with first prize. Except, perhaps, doing it twice. In January, the QNX-based Chevy MyLink system earned a Best of CES 2013 Award, in the car tech category. And in May, it pulled another coup: first place in the "Automotive, LBS, Navigation & Safe Driving" category of the 2013 CTIA Emerging Technology (E-Tech) Awards.

Panasonic, Garmin, and Foryou get with the platform
Garmin K2 platform: because
one great platform deserves
another.
August was crazy busy — and crazy good. Within the space of two weeks, three big names in the global auto industry revealed that they’re using the QNX CAR Platform for their next-gen systems. Up first was Panasonic, who will use the platform to build systems for automakers in North America, Europe, and Japan. Next was Foryou, who will create infotainment systems for automakers in China. And last was Garmin, who are using the platform in the new Garmin K2, the company’s infotainment solution for automotive OEMs.

And if all that wasn’t cool enough…

Mercedes-Benz showcases the platform
Did I mention I want one?
When Mercedes-Benz decides to wow the crowds at the Frankfurt Motor Show, it doesn’t settle for second best. Which is why, in my not so humble opinion, they chose the QNX CAR Platform for the oh-so-desirable Mercedes-Benz Concept S-Class Coupé.

Mind you, this isn’t the first time QNX and Mercedes-Benz have joined forces. In fact, the QNX auto team and Mercedes-Benz Research & Development North America have collaborated since the early 2000s. Moreover, QNX has supplied the OS for a variety of Mercedes infotainment systems. The infotainment system and digital cluster in the Concept S-Class Coupé are the latest — and arguably coolest — products of this long collaboration.

We create noise to eliminate noise
Taking a sound approach to
creating a quieter ride.
Confused yet? Don’t be. You see, it’s quite simple. Automakers today are using techniques like variable cylinder management, which cut fuel consumption (good), but also increase engine noise (bad). Until now, car companies have been using active noise control systems, which play “anti-noise” to cancel out the unwanted engine sounds. All fine and good, but these systems require dedicated hardware — and that makes them expensive. So we devised a software product, QNX Acoustics for Active Noise Control, that not only out-performs conventional solutions, but can run on the car’s existing audio or infotainment hardware. Goodbye dedicated hardware, hello cost savings.

And we flub our lines on occasion
Our HTML5 video series has given companies like Audi, OnStar, Gartner, TCS, and Pandora a public forum to discuss why HTML5 and other open standards are key to the future of the connected car. The videos are filled with erudite conversation, but every now and then, it becomes obvious that sounding smart in front of a camera is a little harder than it looks. So what did we do with the embarrassing bits? Create a blooper reel, of course.

Are these bloopers our greatest moments? Nope. Are they among the funniest? Oh yeah. :-)

Tuesday, October 8, 2013

A sound approach to creating a quieter ride

Tina Jeffrey
Add sound to reduce noise levels inside the car. Yup, you read that right. And while it may seem counterintuitive, it’s precisely what automakers are doing to provide a better in-car experience. Let’s be clear: I’m not talking about playing a video of SpongeBob SquarePants on the rear-seat entertainment system to keep noisy kids quiet — although I can personally attest to the effectiveness of this method. Rather, I’m referring to deliberately synthesized sound played over a vehicle’s car speakers to cancel unwanted low-frequency engine tones in the passenger compartment, yielding a quieter and more pleasant ride.

So why is this even needed? It comes down to fuel economy. Automakers are continually looking at ways to reduce fuel consumption through techniques such as variable cylinder management (reducing the number of cylinders in operation under light engine load) and operating the engine at lower RPM. Some automakers are even cutting back on passive damping materials to decrease vehicle weight. These approaches do indeed reduce consumption, but they also result in more engine noise permeating the vehicle cabin, creating a noisier ride for occupants. To address the problem, noise vibration and harshness engineers (OEM engineers responsible for characterizing and improving sound quality in vehicles) are using innovative sound technologies such as active noise control (ANC).

Automotive ANC technology is analogous to the technology used in noise-cancelling headphones but is more difficult to implement, as developers must optimize the system based on the unique acoustic characteristics of the cabin interior. An ANC system must be able to function alongside a variety of other audio processing tasks such as audio playback, voice recognition, and hands-free communication.


The QNX Acoustics for Active Noise Control solution uses realtime engine data and sampled microphone data from the cabin to construct the “anti-noise” signal played over the car speakers.

So how does ANC work?
According to the principle of superposition, sound waves will travel and reflect off glass, the dash, and other surfaces inside the car; interfere with each other; and yield a resultant wave of greater or lower amplitude to the original wave. The result varies according to where in the passenger compartment the signal is measured. At some locations, the waves will “add” (constructive interference); at other locations, the waves will “subtract” or cancel each other (destructive interference). Systems must be tuned and calibrated to ensure optimal performance at driver and passenger listening positions (aka “sweet spots”).

To reduce offending low-frequency engine tones (typically <150 Hz), an ANC system typically requires real-time engine data (including RPM) in addition to signals from the cabin microphones. The ANC system then synthesizes and emits “anti-noise” signals that are directly proportional but inverted to the original offending engine tones, via the car’s speakers. The net effect is a reduction of the offending tones.


According to the superposition principle of sound waves, a noise signal and an anti-noise signal will cancel each other if the signals are 180 degrees out of phase. Image adapted from Wikipedia.

Achieving optimal performance for these in-vehicle systems is complex, and here’s why. First off, there are multiple sources of sound inside a car — some desirable and some not. These include the infotainment system, conversation between vehicle occupants, the engine, road, wind, and structural vibrations from air intake valves or the exhaust. Also, every car interior has unique acoustic characteristics. The location and position of seats; the position, number, and type of speakers and microphones; and the materials used inside the cabin all play a role in how an ANC system performs.

To be truly effective, an ANC solution must adapt quickly to changes in vehicle cabin acoustics that result from changes in acceleration and deceleration, windows opening and closing, changes in passenger seat positions, and temperature changes. The solution must also be robust; it shouldn’t become unstable or degrade the audio quality inside the cabin should, for example, a microphone stop working.

The solution for every vehicle model must be calibrated and tuned to achieve optimal performance. Besides the vehicle model, engine noise characteristics, and number and arrangement of speakers and microphones, the embedded platform being used also plays a role when tuning the system. System tuning can, with conventional solutions, take months to reach optimal performance levels. Consequently, solutions that ease and accelerate the tuning process, and that integrate seamlessly into a customer’s application, are highly desirable.

Automotive ANC solutions — then and now
Most existing ANC systems for engine noise require a dedicated hardware control module. But automakers are beginning to realize that it’s more cost effective to integrate ANC into existing vehicle hardware systems, such as the infotainment head unit. This level of integration facilitates cooperation between different audio processing tasks, such as managing a hands-free call and reducing noise in the cabin.

Earlier today, QNX announced the availability of a brand new software product that targets ANC for engine tone reduction in passenger vehicles. It’s a flexible, software-based solution that can be ported to floating or fixed-point DSPs or application processors, including ARM, SHARC, and x86, and it supports systems with or without an OS. A host application that executes on the vehicle’s head unit or audio amplifier manages ANC through the library’s API calls. As a result, the host application can fully integrate ANC functionality with its other audio tasks and control the entire acoustic processing chain.

Eliminating BOM costs
The upshot is that the QNX ANC solution can match or supersede the performance of a dedicated hardware module — and we have the benchmarks to show it. Let me leave you with some of the highlights of the QNX Acoustics for Active Noise Control solution:

  • Significantly better performance than dedicated hardware solutions — The QNX solution can provide up to 9dB of reduction at the driver’s head position compared to 5dB for a comparative hardware solution in the same vehicle under the same conditions.
     
  • Significant BOM cost savings — Eliminates the cost of a dedicated hardware module.
     
  • Flexible and configurable — Can be integrated into the application processor or DSP of an existing infotainment system or audio amplifier, and can run on systems with or without an OS, giving automakers implementation choices. Also supports up to 6 microphone and 6 speaker-channel configurations.
     
  • Faster time to market — Speeds development by shortening tuning efforts from many months to weeks. Also, a specialized team of QNX acoustic engineers can provide software support, consulting, calibration, and system tuning.

For the full skinny on QNX Acoustics for Active Noise Control, visit the QNX website.