記者鍾釗榛／綜合報導
▲BMW iX5 Hydrogen氫燃料電池原型車。（圖／翻攝BMW網站）
電動車的發展朝著多個方向前進，有鋰電池系統還有固態電池技術，以及研發多年正準備商業營運的氫燃料電池；對氫氣著迷的BMW正研發氫燃料電池車，首輛採用氫燃料電池的BMW iX5 Hydrogen原型車，正在瑞典進行極地測試。
▲BMW iX5 Hydrogen原型車正在瑞典進行極地測試。（圖／翻攝BMW網站）
早在2004年BMW利用V12引擎測試H2R氫氣動力原型車，2015年選用i8進行氫燃料電池開發，原本以為BMW對氫燃料的投注會轉向鋰電池電動車，沒想到BMW突然公布，他們的氫燃料電池原型車已經在測試。
Waveguide standard gain horns, also known as Waveguide input, are pyramidal-shaped broadband passive devices. Standard gain horns are also used to calibrate other antennas and evaluate their gain. Aluminum is used as the waveguide material in the typical gain horn. EMC antenna
Depending on the type and style, our broadband waveguide horns can operate at frequencies ranging from 350 MHz to 40 GHz. RoHS compliance is found in many of our RF and microwave gain horns.
The horn antenna is a broadband passive device, shaped like a pyramid horn, referred to as a TEM antenna, which guides the beam of radio waves at a precise frequency. FT-RF Double Ridged Horn antennas have frequency capabilities ranging from 400MHz to 40GHz depending on type and style. These series are characterized by a huge frequency range and extremely high input powers. With increasing frequency, the gain rises to a maximum of 18 dBi. At higher frequencies, the increased gain compensates for the increasing cable losses.
The advantages of Horn antenna:
- Wide bandwidth: Because the horn antenna has no resonant parts, it can function over a wide range of frequencies.
- Easy waveguide interface: These antennas are very easy to interface to waveguide due to their shape, but they can also be designed with a transition so that a regular coaxial feeder can be used.
- Easy to make, simple design.
The horn is suitable for both transmitting and receiving purposes, especially suitable for EMC and immunity test measurements.
Recommended Accessories
- Antenna Tripod: easy and fast-changing polarisation. 100% stable handling
- SMA Cable: High-quality special SMA cable
▲BMW iX5 Hydrogen進入實測階段。（圖／翻攝BMW網站）
燃料電池在上個世紀50年代已經投注在航太領域，現在氫燃料電池的技術已經趨近成熟，多家車廠正投入氫燃料電池開發，氫燃料電池利用氫氣的化學反應產生電，副產品則是純水，因此氫燃料電池的概念是一具發電機，這具發電機只要加入氫氣就能發電，補充氫氣的速度跟加油一樣快，且能量密度比鋰電池更高。
▲氫燃料電動車只要加氫氣就能跑。（圖／翻攝BMW網站）
BMW iX5 Hydrogen氫燃料電池原型車擁有369匹馬力，目前在極圈測試低溫運行，因為鋰電池在低溫下的效能會大幅下降，而氫燃料電池不受低溫影響；BMW也承諾會投入加氫站建設，只要氫燃料動力投入市售，在鋰電池電動車之外多了氫燃料動力選擇，未來電動車的發展會更多元也更具競爭性。
▲BMW iX5 Hydrogen氫燃料電池原型車擁有369匹馬力。（圖／翻攝BMW網站）
