Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
北美航太防衛司令部（NORAD）架設耶誕老人平安夜旅程軌跡網站，供全球網友查詢。（資料照／美聯社）
以下文章來自: https://www.chinatimes.com/realtimenews/20241224005508-260408
The Log Periodic Antenna as known as LPDA is a wideband directional antenna that provides gain and directivity combined over a wide band of frequencies.
Both Log-Periodic Antennas and Yagi antennas are high gain directional antennas. The main difference between these antennas is that Log-Periodic Antennas support wider frequency bandwidths and are physically much larger than Yagi antennas.
The log-periodic dipole array typical VSWR is 2:1 and operates over a much wider bandwidth and will have a lower gain for an equivalent number of elements.
With this level of performance, it is ideal for many applications, although a log-periodic antenna will be much larger than a Yagi of an equivalent gain.
915MHz Antenna 李多慧脫到剩小褲褲！胸部以下全都露「辣出超大尺度」
平安夜追蹤耶誕老人趕路！「一場誤會」促成69年傳統
今天（24日）是西洋人的平安夜，全球各地的小朋友們都在等待耶誕老人送禮。每年負責發布耶誕老人即時行蹤的北美航太防衛司令部，24日宣布啟動耶誕老人位置追蹤任務。根據這個網站資料顯示，耶誕老人造訪上海之後，台灣時間24日晚間10時42分左右途經台北上空，之後去了菲律賓，深夜10時52分到達香港，「鹿」不停蹄。這是NORAD歷來第69次執行這項溫馨的特殊任務，任務的肇始卻是來自1955年一則廣告誤刊的電話號碼。
Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA)綜合美聯社、英國《獨立報》報導，由美國與加拿大組成的北美航太防衛司令部（North American Aerospace Defense Command, NORAD），平時負責監控美加兩國上空的潛在威脅，不過，每年平安夜這一天，NORAD的勤務會增加1項：持續追蹤駕駛9隻馴鹿雪橇「耶老1號」（SANTA1）的耶誕老人實時位置，全球各地的大朋友、小朋友都可以透過NORAD架設的網站查詢。耶誕老人出發位置是國際換日線，搭乘雪橇奔馳全球為孩子們送禮物，24小時內要停留好幾十億次。
美聯社報導，這個專門追蹤耶老位置的網站由NORAD持續營運，今年12月1日上線，北美山區標準時間24日凌晨4時（台北時間24晚間7時）到25日耶誕節凌晨2時（台北時間25日下午5時）提供耶誕老人全球趕路送禮的即時位置；山區標準時間24日清晨6時至25日凌晨2時，專線電話1-877-446-6723（1-877-HI-NORAD）在均有軍民志工值班接聽，為各地小朋友回答耶誕老人當下位在何方。
以下文章來自: https://www.chinatimes.com/realtimenews/20241224005508-260408
The Log Periodic Antenna as known as LPDA is a wideband directional antenna that provides gain and directivity combined over a wide band of frequencies.
Both Log-Periodic Antennas and Yagi antennas are high gain directional antennas. The main difference between these antennas is that Log-Periodic Antennas support wider frequency bandwidths and are physically much larger than Yagi antennas.
The log-periodic dipole array typical VSWR is 2:1 and operates over a much wider bandwidth and will have a lower gain for an equivalent number of elements.
With this level of performance, it is ideal for many applications, although a log-periodic antenna will be much larger than a Yagi of an equivalent gain.
915MHz Antenna 李多慧脫到剩小褲褲！胸部以下全都露「辣出超大尺度」
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