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| The iPhone is a great device, but still a lousy phone | InfoWorld |
Across the board — from Motorola's Droid X to the BlackBerry Torch — Consumer Reports gave most smart phones "fair" voice quality ratings in its latest reviews. The same trend is evident in reviews going back a few years. That's in stark contrast to the "excellent" ratings given to display, Web browsing and even battery life features on smart phones.verall Wireless Call Quality Momentum Halts - J.D. Power and Associates
"It seems that voice quality has been neglected. It's adequate. Most of the phones we test — the voice quality hovers between good and poor," says Mike Gikas, the senior electronics editor for Consumer Reports. "It's probably the only area where cell phones aren't making any headway in terms of improvements."
The semiannual study measures wireless call quality based on seven problem areas that impact overall carrier performance:Why Mobile Voice Quality Still Stinks—and How to Fix It - IEEE Spectrum
1 dropped calls;
2 static/interference;
3 failed call connection on the first try;
4 voice distortion;
5 echoes;
6 no immediate voicemail notification; and
7 no immediate text message notification.
Call quality issues are measured as problems per 100 (PP100) calls, where a lower score reflects fewer problems and higher call quality. Call quality performance is examined in six regions: Northeast; Mid-Atlantic; Southeast; North Central; Southwest; and West.
among wireless customers who use data-intensive devices such as smartphones or who have high texting activity, problem rates are higher than the industry average. Problem rates among users of smartphones average 13 PP100, while problem rates average 14 PP100 among heavy texters. These shifts in usage patterns have slowed the historic improvement in call quality, which steadily improved between 2003 and 2009. However, during the past two years, there has not been a significant change in overall call quality performance across the industry.
Laboratory tests by Broadcom confirm that it’s not just my aging ears: Even in the best conditions, including a quiet environment and a strong wireless signal, users consistently rate voice quality lower on a cellphone than on a landline. Weaken the cellular link or add background noise, such as from wind or street traffic, and callers’ opinions of the experience drop dramatically.Voice Quality Testing Across All Networks
Most cellular voice traffic today passes through a patchwork of diverse systems, each exchange point an opportunity for degradation and delays. But lest you despair, here’s some good news: Solutions to many of these impediments are in the works or already available, including a standard known as HD voice or wideband audio, and an add-on to today’s 4G LTE systems called Voice over LTE.
The first obstacle to a good-quality voice connection on today’s mobile phones is their design. The smartphone’s form “is driven by industrial design and not voice quality,” says Chris Kyriakakis, founder and chief technology officer of Audyssey, a Los Angeles–based acoustic design company.
smartphone designers shrink and flatten speakers and sometimes even cover them in plastic, and thus have to use software to lessen distortions, making voices sound more realistic. Your smartphone’s puny microphone is similarly problematic.
Yet even if your cellphone distills crisp, noise-free speech, there’s no guarantee it will arrive at the listener intact. The next threat comes when the phone transmits the call to a base station. Modeled after standard wire-line phones, most mobile phones today digitize audio frequencies from 300 to 3,400 hertz. But unlike landlines, which provide each caller with a dedicated, full-capacity channel, cellphones must share a limited amount of wireless spectrum. So they compress the voice data to let more users connect. Standard compression rates vary from 12.2 kb/s to 4.75 kb/s, depending on the volume of voice traffic and the strength of the wireless signal. Calls compressed to speeds as low as 7.95 kb/s can still sound almost as good as a landline connection. But beyond that, “you start to hear compression artifacts,” including missing syllables and distortions such as ringing or warbling.
Voice over LTE (VoLTE) lets cellular carriers send voice calls the same way they send other data, like bits of a streaming video. As VoIP services do, VoLTE compresses and digitizes your voice, sending it as packets of data over the LTE network. The packets are sent with priority codes to ensure they arrive in order and don’t garble your message. LTE is now widely available, but carriers still have work to do to ensure that all networks respect one another’s priority codes.
Meanwhile, carriers are expanding their IP infrastructures, including backbone networks and local broadband links, which will let VoLTE packets flow seamlessly between mobile handsets and other IP phones, including computers and landlines. Voice quality should continue to improve as more networks support priority protocols and callers move onto the same packet-based system.
The VQuad™ (Voice Quad) software is used to automatically send and record voice files from four different types of network (Quad meaning 4 networks: Wireless, VoIP, TDM, & Analog). VQuad™ supports up to 8 telephony devices simultaneously. A minimum of two telephony nodes are required for transferring files and these nodes may be configured together on a single PC, or with each node served by one PC.Broadcom's Revolutionary M-Stream Technology Delivers Vastly Superior Voice Quality in Upcoming Palm® Treo™ 680
The system is designed for easier, portable, and convenient testing. The system provides all necessary capability for automatic measurement of Voice Quality and QOS for any desired network including Wireless (Bluetooth®, Wi-fi, 3G, 4G, LTE), VoIP, Analog, and TDM.
First Commercial Deployment of Broadcom's M-Stream Technology Also Demonstrates Enhanced Signal Quality in Poor Cellular Coverage
IRVINE, Calif., Nov 09, 2006 -- Broadcom Corporation (Nasdaq: BRCM), a global leader in semiconductors for wired and wireless communications, today announced that the new Palm® Treo™ 680 smartphone is the first commercial cell phone to implement M-Stream technology from Broadcom. M-Stream technology provides significant improvements in handset reception and voice quality over legacy cell phones for no additional bill of materials (BOM) cost, and without the need for an upgrade or modifications to an existing network infrastructure. The Palm Treo 680 is the third Treo model to integrate Broadcom's baseband processors and industry-leading Bluetooth® solution, and now added M-Stream technology to deliver enhanced user experience through higher voice quality and larger coverage area.
With fewer dropped calls and a noticeable improvement in the quality of voice communications, M-Stream provides consumers with an enhanced mobile phone experience. Utilizing M-Stream technology enables the new Palm Treo 680 to offer dramatically better voice quality compared to other handsets without increasing the overall BOM cost. In addition, the technology enables network operators to maintain call quality while nearly doubling existing cellular network capacity without requiring costly infrastructure upgrades.
How We Test Cell Phones and Smartphones
3 reasons voice quality on smart phones still sucks
It's a miracle you can hear anything at all
1. They're space-challenged
When it comes to sound quality, cordless phones have it easy. They have only one primary function—voice calls—and their larger size lets them place their large microphones and speakers as close to your mouth and ear as possible.
Smart phones, on the other hand, are a technological sausage, densely packed with cameras, radios, microprocessors, sensors, and other hardware that enables them to do all those amazing things we expect them to do. Often, the tiny speaker is wedged between the bezel and the front-facing camera, while the microphone is sometimes relegated to the bottom of the phone—or the back. That almost guarantees a less-than-ideal connection with your mouth and ear.
2. The signals travel a long and winding road
Every second of a cellular voice call is a scientific miracle. What you say and hear is shredded into tiny pieces called packets that hitch a ride on microwave signals until they're reassembled by the phone of the person to whom you are speaking.
As those signals jump from cell tower to cell tower, they run into trees, mountains buildings, the weather, and other obstacles that cause them to split. The split signals produce a phenomenon called multipath, when multiple copies of the same signal reach your smart phone at different times, like an echo.
Deciphering multipath signals is quite difficult, and when the phone gets overwhelmed, the signal has to be retransmitted. Of course, few people notice because all of this happens within a fraction of a second. So that's why it's almost miraculous that voice calls sound as clear as they do.
3. They face a lot of competition
Part of a cell phone's appeal is that you can take them everywhere. Unfortunately everywhere is often a noisy place, filled with the din of traffic, rude conversations, and the sweet, distracting sounds of Mother Nature. Some phone makers brag about the noise-canceling technologies they've shoehorned into their devices, but they rarely make a significant difference, according to our tests.
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