liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
High-Speed Downlink Shared Channel in Unlicensed Frequency Bands
Linköping University, Department of Electrical Engineering.
2004 (English)Independent thesis Basic level (professional degree)Student thesisAlternative title
HS-DSCH i olicensierade frekvensband (Swedish)
Abstract [en]

In the standardized air interface for third generation mobile communication systems, WCDMA release 5, a concept called High Speed Downlink Packet Access (HSDPA) is introduced. HSDPA enables faster transmissions from base stations to mobile users by using a shared, high-capacity channel called the High-Speed Downlink Shared Channel (HS-DSCH) that is designed for best effort services. The HS-DSCH is developed for usage in the frequency band licensed for third generation communication systems. As the use of licensed frequency bands is costly it may be interesting to make use of the unlicensed frequency bands at 2.4 GHz and 5 GHz with higher interference and stricter regulations. Using HS- DSCH in unlicensed frequency bands would lead to smaller costs and a new kind of usage of the HS-DSCH.

In order to transmit in unlicensed frequency bands, some requirements set up by the public authorities must be followed. This means that the maximum transmit power used by the HS-DSCH must be decreased and, on the 5 GHz frequency band, that features to avoid disturbing radar systems have to be implemented. The HS- DSCH has a bandwidth of 5 MHz. To use the available frequency spectra more efficiently, multiple carriers could be used.

Wireless Local Area Networks (WLANs) are the most common way to transfer data in unlicensed frequency bands today. Assessments and simulations of WLAN and the HS-DSCH in unlicensed frequency bands show that WLAN can provide higher bitrates than the HS-DSCH for low loads. HS-DSCH can however provide a larger coverage per base station, and is more bandwidth effective than WLAN. Using a larger bandwidth is necessary for HS-DSCH to compete with WLAN, which uses a bandwidth approximately four times as large as the HS-DSCH bandwidth. The usage of the HS-DSCH in unlicensed frequency bands also has the advantage that the services provided by the third generation communication systems can be accessed easily.

Place, publisher, year, edition, pages
Institutionen för systemteknik , 2004. , 72 p.
LiTH-ISY-Ex, 3490
Keyword [en]
Reglerteknik, HSDPA, HS-DSCH, unlicensed frequency bands, UMTS, WCDMA
Keyword [sv]
National Category
Control Engineering
URN: urn:nbn:se:liu:diva-2175OAI: diva2:19505
Available from: 2004-03-08 Created: 2004-03-08

Open Access in DiVA

fulltext(673 kB)572 downloads
File information
File name FULLTEXT01.pdfFile size 673 kBChecksum MD5
Type fulltextMimetype application/pdf

By organisation
Department of Electrical Engineering
Control Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 572 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 556 hits
ReferencesLink to record
Permanent link

Direct link