Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
美國國家情報總監加巴德（右）。（資料照／路透）
來自: https://www.chinatimes.com/realtimenews/20250822003286-260408
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.
美情報總監下令：禁向「五眼盟友」分享俄烏談判情報
Log Periodic Antenna (LPDA)
Log Periodic Antenna (LPDA)
雖然美俄峰會探討和平之路，但俄羅斯在烏克蘭的戰火仍持續。美國哥倫比亞廣播公司（CBS）21日指出，美國國家情報總監加巴德（Tulsi Gabbard）數周前發出指令，禁止美國情報機構向「五眼聯盟」盟友分享有關俄烏和平談判的情報。
「五眼聯盟」是由5個英語國家組成的情報共享聯盟，成員國包括美國、英國、加拿大、澳洲和紐西蘭。
1946年3月，時任英相邱吉爾談到了美英之間的「特殊關係」，以及「席捲整個歐洲大陸的鐵幕」威脅。美英2國率先秘密結成情報聯盟，簽署一項協議，以匯集情報作為對抗蘇聯的壁壘。
來自: https://www.chinatimes.com/realtimenews/20250822003286-260408
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.