| Author | Bancha Kewkomkum |
| Call Number | AIT Thesis no.TC-97-16 |
| Subject(s) | Artificial satellites in telecommunication
|
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering. |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. TC-97-16 |
| Abstract | The integration of LEO satellite mobile systems and terrestrial cellular networks is a very relevant issue. There has been an exponential growth in mobile teletraffic in recent years. Thus, the integration of these two systems is a natural extension. An integration is proposed between LEO satellite system and a hierarchical terrestrial cellular system having two individual levels. The LEO satellite spot beam as the highest level overlays two terrestrial cellular cells that are macrocell and microcell respectively. The integration is considered as transfer of overflowed calls among the levels. The overflow can occur in two ways: a new call or a handover call within the lowest level are transfered to higher levels if no free channel is available. Similarly, calls can be reverted back to lower levels if free channels are available. Discrete Event Simulation method is selected to evaluate the performance of such an integration system. Simulation performances are computed and shown as blocking probabilities, handover failure probabilities, forced termination probabilities, carried traffic, and channel utilization. The thesis proposes the system performance enhancement of a reversible scheme over a nonreversible scheme. Nonreversible scheme allows the call that is served at certain level can only continue service at the same level or overflow to higher level. On the other hand, a reversible scheme permits the call to return down to lower level when an available channel in lower level is found. Moreover four types of handover strategies are used to a reversible scheme: nonprioritized scheme, guard channel handover scheme, queuing handover scheme, and guard channel with queuing scheme. All schemes other than the nonprioritized schemes, improve the system performance with regard to handover calls management. The more is the degree of handover prioritization the more is the increase of blocking probability. Consequently, the number of channels kept to handover is an important design parameter, and it must be carefully chosen in compromising with blocking probability to specify the network requirement. |
| Year | 1997 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. TC-97-16 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Telecommunications (TC) |
| Chairperson(s) | Ahmed, Kazi M. |
| Examination Committee(s) | Chindakorn Tuchinda;Jian Guo Zhang |
| Scholarship Donor(s) | Jasmine Telecom Systems Co.,Ltd. |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1997 |