Sökning: "Narrow Bipolar Pulses"

Hittade 5 avhandlingar innehållade orden Narrow Bipolar Pulses.

  1. 1. Interaction of Lightning Flashes with Wireless Communication Networks : Special Attention to Narrow Bipolar Pulses

    Författare :Mohd Riduan Ahmad; Vernon Cooray; Mahbubur Rahman; Rajeev Thottappillil; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; Latitude; Lightning; Narrow bipolar pulse; Wireless network.; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Sammanfattning : In this thesis, the features of electric field signatures of narrow bipolar pulses (NBPs) generated by cloud flashes are investigated and their effects on wireless communication systems are studied. A handful amount of NBPs (14.5%) have been observed to occur as part of cloud-to-ground flashes in South Malaysia. LÄS MER

  2. 2. Broadband and HF Radiation from Cloud Flashes and Narrow Bipolar Pulses

    Författare :Noor Azlinda Ahmad; Vernon Cooray; Farhad Rachidi; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Lightning; Cloud Flashes; Narrow Bipolar Pulses; HF radiation; Other physics; Övrig fysik; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Sammanfattning : Remote measurement of electric field generated by lightning has played a major role in understanding the lightning phenomenon. Even though other measurements such as photographic and channel base current have contributed to this research field, due to practical reasons remote measurements of electric field is considered as the most useful tool in lightning research. LÄS MER

  3. 3. Broadband and HF radiation from cloud flashes and narrow bipolar pulses

    Författare :Noor Azlinda Ahmad; Uppsala universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Remote measurement of electric field generated by lightning has played a major role in understanding the lightning phenomenon. Even though other measurements such as optical, photographic, channel base current and thunder signatures have contributed in this regards, due to practical reasons remote measurements of electric field is considered as the most useful tool in lightning research. LÄS MER

  4. 4. Temporal and Wavelet Characteristics of Initial Breakdown and Narrow Bipolar Pulses of Lightning Flashes

    Författare :Mona Riza Mohd Esa; Vernon Cooray; Mahbubur Rahman; Farhad Rachidi; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; Initial breakdown; Lightning flash; Narrow bipolar pulse; Temporal-Wavelet characterization; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Sammanfattning : Temporal and wavelet characteristics of initial breakdown pulses are meticulously studied especially during the earliest moment of lightning events. Any possible features during the earliest moment that may exist which lead to either negative cloud-to-ground (CG), positive cloud-to-ground, cloud or isolated breakdown flashes in Sweden are investigated. LÄS MER

  5. 5. Features and Origin of Electromagnetic Fields Generated by Lightning Flashes

    Författare :Mohd Muzafar Ismail; Vernon Cooray; Farhad Rachidi; Uppsala universitet; []
    Nyckelord :negative cloud-to-ground lightning flashes; HF and VHF radiation; chaotic pulse trains; lightning initiation; zero-crossing time; electromagnetic fields; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Sammanfattning : Negative cloud-to-ground (CG) lightning flashes transport negative charge from cloud to ground. Negative ground flashes typically involve various processes identified as preliminary breakdown, stepped leader, return stroke, dart leader, dart-stepped leader, subsequent return stroke, and cloud activity between strokes, such as regular pulse trains and chaotic pulse trains. LÄS MER