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Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
模擬火星與太空生活的CHAPEA任務在星期六結束，4名太空人結束1年多的封閉生活，指揮官哈斯頓與其他3人說明自己的感想。 (圖/美聯社)
建造中的CHAPEA艙室，由模擬火星砂土的材料，以3D列印方式建造。(圖/NASA)
引用自: https://www.chinatimes.com/realtimenews/20240708004410-260408
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.
NASA火星模擬任務結束 4名受試者健康情況良好
Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA)美國太空總署火星任務的4名機組人員，經過一年的星際航行後，終於在星期六抵達地球，他們的狀態還算良好。這場任務稱為「組員健康和性能探索模擬」(Crew Health and Performance Exploration Analog, 簡稱CHAPEA)，4名船員是在高度設計的外星環境居住一年，實驗在封閉環境中的維生系統，是否可以長期運作。
美聯社報導，YY凱莉哈斯頓(Kelly Haston)、安卡謝拉劉(Anca Selariu)、羅斯布洛克威爾(Ross Brockwell) 和納森瓊斯(Nathan Jones)於 2023 年 6 月 25 日，進入利用 3D 列印技術製作的類火星殖民地，他們在星期六完成任務離開人造環境。
任務指揮官哈斯頓在出艙時，以簡單的「Hello」與大家打招呼，彷彿她剛從火星回來。
瓊斯是一名醫生兼任務醫療官，他說「這 378 天的封閉生活，其實過得很快。」
四人在157平方公尺的環境內生活和工作，模擬前往紅色星球(火星)的行程；火星距離太陽第四顆，是除月球之外，科學家和科幻迷們最常討論的可能星際航行地點，它的距離與環境也是現今科技比較能克服的。
引用自: https://www.chinatimes.com/realtimenews/20240708004410-260408
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.
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