Mobile-phone antenna design

published_or_final_versio

Uncommon ossicle in Holothuria (Mertensiothuria) leucospilota from Teluk Nipah, Pangkor Island

The high popularity of a commercial sea cucumber species on Pangkor Island (i.e. Stichopus horrens) has resulted in a lack of studies on Holothuria (Mertensiothuria) leucospilota from Pangkor Island, Perak, Malaysia. S. horrens is the main ingredient of gamat-based traditional medicine on the resort island, while H. leucospilota is the most dominant species. For that reason, this study aimed to isolate ossicles from a specimen of morphospecies H. leucospilota collected from Teluk Nipah Beach, Pangkor Island; and to determine the shapes of the ossicles for species verification. A number of six ossicle shapes were observed. Beside buttons and tables as the common ossicle shapes; I-shaped rod, long I-shaped rod, branched rod, and spider-shaped rod were also documented. Nonetheless, the spider-shaped rod is an unusual ossicle shape in H. leucospilota as there was no previous record on it, thus it could be considered as a new finding. In summary, the results of this research indicate the uniqueness of the specimen of morphospecies H. leucospilota as a result of the presence of the spider-shaped rod. More studies with more samples, more morphological approaches as well as more molecular techniques need to be incorporated in future for a better insight

Mobile-phone antenna design

published_or_final_versio

Study of multi-antenna terminals in the presence of close scatterers

Projecte final de carrera realitzat en col.laboració amb ENSTA ParisTechMulti-antenna technologies may offer significant increases in data throughput and link range without additional bandwidth or transmit power by using spatial diversity concept. However, the radiation proprieties and return loss of these antennas as well as the channel capacity may be modified by many factors such as close scatterers (human body), mutual coupling, PCB housing, etc. The goal of this study is to characterize the behavior of some multi-antenna prototypes in the presence of these perturbation sources. Most of the antennas are designed to work for 2.4/5.2/5.8 GHz WLAN bands and 2.5/3.5/5.5GHz WiMAX bands and are printed on PCBs of size 114x64 mm2 which follow the average dimensions of PDAs found in the market. Different antennas were designed, simulated and fabricated. In Chapter 4 the results for the circular monopole array antenna is widely detailed. In the Appendix, designs of other antennas simulated and/or fabricated are shown