Beamforming using tapped delay line filters for broadband CDMA systems | |
| Author | Hossain, Md. Anwar |
| Call Number | AIT Thesis no.ICT-06-11 |
| Subject(s) | Code division multiple access Antenna arrays |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ICT-06-11 |
| Abstract | Next generation wireless code division multiple access (CDMA) systems are expected to support transmission rates beyond those currently achieved by second and third generation systems. Antenna arrays are known to improve the transmission performance of CDMA systems. For broadband CDMA networks, the optimal signal processing for antenna arrays needs to be frequency selective. This thesis investigates the performance of uncoded uplink transmissions in broadband CDMA systems with tapped delay line (TDL) antenna arrays. The weights of TDL are derived for broadband CDMA systems. Through simulations, demonstration has been given how TDL antenna arrays can help reduce multiaccess interference (MAI), allow the use of spreading codes with higher correlation, and increase the number of supportable users. Using the two-ray channel model and assuming that users are located at the angles uniformly distributed around the base station, the number of antennas and tap delays required to increase the number of supportable users from 15 in the baseline case with small Kasami spreading codes and the uncoded bit error rate (BER) of 10-3 to 30, 60, and 120 users with large Kasami spreading codes respectively are identified. Two antennas and four taps each can support 30 users with uncoded BER of 10-3 at 20 dB SNR. Three antennas and six taps each can support 60 users with BER less than 10-3 at 20 dB SNR. Finally, eight antennas and sixteen taps each can support 120 users with BFR less than l0-3 at 20 dB SNR. |
| Year | 2006 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ICT-06-11 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Information and Communication Technology (ICT) |
| Chairperson(s) | Poompat Saengudomlert |
| Examination Committee(s) | Rajatheva, R.M.A.P.; Ahmed, Kazi M. |
| Scholarship Donor(s) | Government of Finland;Asian Institute of Technology Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2006 |