SINGAPORE (09/26/2003) - Can the next big thing in wireless be blown off course by the humble hair dryer? That is what the Infocomm Development Authority (IDA) of Singapore aims to find out as it studies the effects of ambient noise on ultra wideband (UWB), and UWB's impact on existing wireless systems such as mobile cellular networks and fixed satellite downlinks.
Speaking at the 10th Infocomm Horizons Seminar organized by the Institute for Infocomm Research, Tan Geok Leng, director for Enabler and Network Technologies, IDA, said plans are underway to collect accurate, island-wide measurements of noise levels present in unoccupied frequency bands in Singapore.
Citing studies that have been done, he noted that "impulsive noise" can be generated by ordinary appliances. "When you turn on the hair dryer, the emissions generated are not far from the magnitude of the wanted (UWB) signal," he said.
As part of the test and measurement phase of Singapore's UWB roadmap, IDA will also be quantifying the impact of UWB on mobile cellular networks such as GSM (global system for mobile communications), GPRS (general packet radio service) and the 3G WCDMA (wideband code division multiple access) networks. Field measurements will be taken with a local mobile operator, said Tan.
Tests will also be carried out in collaboration with Temasek Polytechnic and the National University of Singapore's Centre for Remote Imaging and Signal Processing to quantify the impact of UWB on C-Band and X-Band fixed satellite downlinks involving the 3.4-4.2GHz and the 7.25-8.4GHz spectrum. The studies will measure the bit error rate as the UWB power level, UWB spectral structure and the number of devices vary.
The tests are expected to be completed by September next year.
Speaking at the same event, Robert Fontana, president of Multispectral Solutions, said interference remains one of the main issues confronting the deployment of UWB systems, especially high data rate systems which generate more energy.
He called for some form of adherence to "spectrum etiquette", which he said was the key to successful UWB commercialization. For example, he said, Multispectral's products operate in the above-6GHz range, out of the lower microwave band.
"Few commercial UWB systems have been fielded to date; thus little is known of the potential for interference to other services," he said. "UWB systems are themselves susceptible to in-band interference from other systems, both UWB and conventional," he added.
Another way of resolving the potential interference issue, he said, is for the United States Federal Communications Commission to move UWB to a higher microwave band, and out of the range of existing cellular and other wireless networks.
In Fontana's view, most of the hurdles to successful UWB commercialization are regulatory in nature, such as the FCC's constraints on power (-41.25dBm/MHz average) and restrictions on the types of applications that are allowed. "Most of these came from a battle over spectrum rights which did not have to exist," he said.
He does not see outdoor applications in UWB emerging any time soon due to FCC restrictions on their deployment. Instead, he said the first UWB applications will probably be in home audio distribution and wireless intercom systems.