Who hasn’t been on an important conference call and heard the infamous “buzz” sound on the speakerphone caused by cell phone interference. Nextel two-way “push to talk” phones are notorious for causing this “buzz” sound, as well as Blackberries. Still don't know what I'm talking about? Sure you do. Just play this MP3 file
and you'll recognize this annoying buzz sound.
As I commented to Polycom, there are occasions when I'm watching FOX News
or some other live TV program and I hear the "buzz" sound during
the TV show that I know is coming from their end. How unprofessional and very annoying. You'd think professional news studios would have shielded microphones, or the news anchors would turn off their cellphone while on the air, but I digress.
I spoke with Jeff Rodman, CTO of Polycom’s Voice Communications Solutions division yesterday. He told me, “10 years the buzz interference wasn’t much of an issue, because not many people had cell phones. But now you can be sitting in a conference table and you can have 5, 10 people sitting around each with 2-3W transmitters in their pocket. The interesting thing is when you get a 2W transmitter within several inches of a phone the fields that the phone sees are as strong as if you had a major radio station 20 or 30 yards away. It’s really quite stunning how quickly the signal strength builds up. So it wasn’t much of an issue years ago, now as you know it’s quite common.”
“RF interference is nothing new, but our awareness of it is at an all-time high, as more and more business is conducted over virtual forms of communications such as voice and video conferencing, and as the popularity of smartphones increases. Now customers can bring their smartphones into the conference room and not cause any interference on the conference call.” He continued, “As the pioneer in voice conferencing, Polycom took the lead in developing solutions that stop the ‘buzz’ and offer the best quality audio available in the industry. Polycom’s industry-leading voice quality, coupled with the new RF shielding and isolation technologies, are now shipping worldwide, helping people be more productive throughout the global workplace.”
I asked Jeff some questions about their buzz-eliminating technology.
Q: What drove Polycom to develop a solution to the buzzing problem?
A: We’ve been going crazy in our own meetings saying ‘what’s that buzzing?’ ‘what’s causing that?’ and then realizing we could do something about to make the meetings better for ourselves but I know we’re not the only one’s suffering from this.
Q: (I commented how cell phones can even send audio out a laptop’s or PC’s speakers.)
A: What happens is there are a lot of things in electronics – it’s operating as a crystal set basically. It detects the modulating waveform and then turns it right back into audio. Essentially, it strips off the radio frequency and just leaves the audio that you hear. So it can happen just in the speaker amplifier -- walk into the amplifier through the speaker leads, be detected, amplified by the amplifier and then go out the PC speakers.
He added: “Telephones and speakerphones have the additional challenge in that they have microphones that typically are putting out a signal that is on the order of millivolts. So if you’ve got several volts per meter of RF field strength it’s not difficult for that to turn into a real signal that gets passed to the other end.”
Q: How do you solve this issue?
A: So one of the things that we spent a lot of time on is working with a couple of our vendors to redesign the microphone element from the ground up to make it highly resistant to this kind of stuff. That’s one of the pieces that goes into our overall solution to the problem.
Q: Can you explain in technical detail exactly how you eliminate the “buzz factor”?
A: It’s really a combination of things. It’s everything from the specific component design. There is an elevated level of shielding – actually metallic shields. There’s a lot of electronic isolation of signals in and out and to some extent within the unit. And then we do a lot of testing. Polycom is a founding member of C63 Study Group 9 of ANSI which is developing a formal industry specification for this. But in the meantime we’ve developed our own kind of superset of that, which is a combination of lab tests with directed microwave amplifiers and directional antennas, and that sort of thing. to really blast the product. As well as a variety of actually real world products that we put in unconventional settings just to be sure that there’s not any situation that we can find where our products are close to having this (buzz) problem.”
Q: Are you doing any sort of noise cancellation of the “buzz” through waveform or spectral analysis?
A: We explored that approach, but we found that we were better off taking a more strongly defensive approach at the beginning to make sure it doesn’t get turned into electricity. So that’s a combination of shielding, signal isolation, EMI filters along signal lines and some of this is even integrated into the microphone that we use, so the RF never gets a chance.
Q: So is this technology going to be rolled out into all of Polycom’s products?
A: We’re going to be rolling this into pretty much all of our upcoming products. All of our IP phone products, all of our circuit-switched products.
Q: Does this add a lot of cost?
A: It does add a little bit to our manufacturing but it doesn’t affect the customer.
On February 5th, Polycom will announced that its analog SoundStation and VoiceStation conference phones now incorporate their advanced radio frequency (RF) shielding technology. This new benefit, will be built into the latest versions of Polycom’s triangular conference phones offering buzz-free conferencing.
As of February 5th, all of Polycom’s analog conference phones will be shipping with this new RF shielding technology, with no changes in price or part numbers. This includes the SoundStation2, SoundStation2W, SoundStation VTX 1000, VoiceStation 300 and 500 product lines. I'm told their VoIP line of conference phones and desktop phones will also incorporate the technology. To learn more about Polycom’s SoundStation and VoiceStation conference phones utilizing RF shielding technology, check out www.nomorebuzz.com/news