Assignment of OVSF Codes in Wideband CDMA
8 Pages1531 Words101 Views
Added on 2020-03-23
Assignment of OVSF Codes in Wideband CDMA
Added on 2020-03-23
ShareRelated Documents
ELEC ENG 4054/7081/7083 TELECOMMUNICATION SYSTEMSASSIGNMENT 2: Wideband CDMAStudent nameStudent registration numberProfessor (tutor)Date of submissionABSTRACTThis paper seeks to determine the scrambling code and the resultant signal strength of the CPICH.The paper defines the scrambling code and its usage as well as the valid channels and their
respective signal strength. The CPICH refers to a fixed rate of 30kbps downlink physical channel. Itcontinuously carries or transmits the pre-determined bit-of-symbol order. It is an uncontrolled codeconduit that is tousled with the cell specified prime scrambling code[ CITATION Tos02 \l 1033 ]. Thechannel aids in the estimation at the end-point for the steadfast channel. It also provides the channelapproximation orientation for the mutual channels such as the PRACH especially when they are notlinked with the dedicated channels.INTRODUCTIONThe common pilot channel, CPICH, is used in the transmission of the carrier responsible forestimating the channel parameters. It acts as a physical reference for the other channels in thewideband CDMA system[ CITATION Har04 \l 1033 ]. Some of its roles include, controlling power,ensuring transmission and coherent detection, performs channel estimates, measurement of adjacentcells and obtaining the scrambling code. Most sections are developing and building and other tallstructures come up all the time. A lot of interference is experienced with regards to thetelecommunication networks. In practice, when the telecommunication engineers and designer setup antennae to serve a given range. Several reports have shown that the UMTS or the commonlyknown, 3G coverage is more interference tolerant as compared to the GSM technologyimplementations[ CITATION Hol05 \l 1033 ]. The antenna may be transmitting signals at ta very high-power level but still the communication could be affected and as a result there is reduction intransmission rate. There has been a great evolution in the mobile communication standards asdefined by the third-generation partnership project, 3GPP. The wideband CDMA is an ultra-terrestrial radio access technology or standard that incorporates both the FDD and the TDDoperations. The evolution is usually based on the improvement of the data transmission rates forboth the uplink and the downlink. There has been a tremendous increase in the number of subscribers locked in WCDMA over the lastdecade. Multiple users are able to send signals to the node B or the Base Station subsystem and the
base propels different signals to diverse users. The system has different sectors such as the turboencoder, inter-leaver or de inter-leaver, OVSF code generator, convolutional encoder, cyclicredundancy checker, and the scrambling code[ CITATION Zha \l 1033 ]. The scrambling code usuallymake the direct sequence CDMA technique have a higher level of efficacy in a multipathenvironment. The code tends to reduce the auto-correlation that occurs between different timedelayed versions of the spreading code. The reduction is such that the receiver can uniquely decryptthe different paths[ CITATION Tos02 \l 1033 ]. These codes separate the users and the base stationsectors from each other by allowing them to individually manage the OVSF tree[ CITATION Van \l1033 ]. The management process is done without coordinating amongst themselves. Thetransmission from different sources are divided by the scrambling codes. The short and longscrambling codes are available[ CITATION Qua \l 1033 ]. The rake receiver determines if the longscrambling codes are to be used in a given base station. The CPICH uses a length of 256 OVSFcode such that during the channelization process, the channels are scrambled with the truncatedGold sequence as shown in the table above. The primary and secondary synchronization channelsare added to the output of scrambling. The PSCH and the SSCH are not orthogonal to the othercodes in the system. This channel uses the spreading factor of 256 chips per symbol and there are10 default pilot symbols in a given channel slot. There is a distinct tradeoff in the CDMA networkin terms of the coverage and capacity. The tradeoff is attributed to the limited power availability forthe users. OBJECTIVES(i)To detect the scrambling code and signal strength of the pilot CPICH(ii)To ascertain the valid channel codes and their respective signal strength(iii)To decrypt the traffic channels and read the enclosed message and demonstrate someopen-ended investigation.DATA ANALYSIS & SIMULATION
End of preview
Want to access all the pages? Upload your documents or become a member.
Related Documents
Wireless Network Conceptslg...
|18
|2132
|232
MIMO Multi-user CDMA System with Forward Error Correctionlg...
|20
|4326
|277
Comparative Performance of Interference Cancellation Techniques in NOMA for Cellular Networkslg...
|23
|3580
|214
Low-Powered IoT Based LPWAN Systems and Cellular Networkslg...
|17
|4107
|142