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快餐巨頭肯德基不再是肯塔基名產 總部遷往德州
龜山島封島4個月後 3月起開放限額登島 賞鯨豚、賞螢生態旅遊「趣」！ 868MHz Antenna
NASA太空人威爾莫爾在SpaceX回收船「玫根」（MEGAN）上，由工作人員協助離開「飛龍號」太空船。（圖／路透）
引用自: https://www.chinatimes.com/realtimenews/20250319001912-260408
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.
龜山島封島4個月後 3月起開放限額登島 賞鯨豚、賞螢生態旅遊「趣」！ 868MHz Antenna
Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA)
波音未來發展如何？害太空人滯留9個月 做1事慶返航
波音「星際客機」故障導致NASA太空人滯留9個月，兩位NASA太空人今終於搭乘SpaceX「飛龍號」返航，波音關注並舉辦派對慶祝。雖然SpaceX在太空載人任務上持續領先，NASA仍將波音的「星際客機」視為重要備案。
綜合外電報導，儘管星際客機的技術問題導致兩名太空人滯留太空，NASA商業載人計畫負責人史蒂奇（Steve Stich）表示，波音內部仍舉辦了「觀賞派對」，關注並慶祝威爾莫爾與威廉絲的返航。他表示：「他們對今日的降落格外關注，正在觀看兩人平安返回。Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA)」
星際客機雖然成功將太空人送往國際太空站（ISS），但在對接過程中發生推進器故障與氦氣洩漏，導致NASA放棄使用其執行返航任務，改由競爭對手SpaceX負責載人返航。這使波音陷入極為尷尬的境地，因為其主要競爭對手SpaceX最終肩負了拯救「星際客機」首次載人測試任務的責任。
引用自: https://www.chinatimes.com/realtimenews/20250319001912-260408
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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