AM Radio BandAM广播频段
The Amplitude Modulated (AM) radio carrier frequencies are in the frequency range 535-1605 kHz. The frequencies 30-535 kHz are used for maritime communication and navigation and for aircraft navigation. Carrier frequencies of 540 to 1600 kHz are assigned at 10 kHz intervals. 幅度调制（AM）无线电载波频率范围为535-1605 kHz。30-535 kHz的频率用于航海通信和导航以及航空导航。540至1600 kHz的载波频率以10 kHz为间隔分配。
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Short Wave短波
The frequencies from the top end of the AM band to the bottom of the VHF television band are generally called the "short wave" range, a historical term. They are part of the general range referred to as "radio frequencies" or RF. The range from 1605 kHz to 54 MHz has multiple communication uses.
The RF frequency range around 40-50 MHz is important as the proton resonance frequency range used in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI). 在40-50 MHz左右的射频频率范围很重要，因为这是质子共振频率范围，用于核磁共振（NMR）和磁共振成像（MRI）。
Electromagnetic spectrum电磁谱 AM频段的高端到VHF电视频段的低端频率通常被称为'短波'范围，这是一个历史术语。它们属于一般称为'无线电频率'或RF的范围。从1605 kHz到54 MHz的频率具有多种通信用途。 |
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TV and FM Radio Band电视和FM广播频段
The carrier frequencies for VHF television Channels 2-4 cover the frequency range 54 to 72 MHz. There is a band from 72-76 MHz which is reserved for government and non-government services, including a standard aeronautical beacon at 75 MHz. VHF TV channels 5 and 6 are between 76 and 88 MHz. The FM radio band is from 88 to 108 MHz between VHF television Channels 6 and 7.Above the FM is a range 108-122 MHz for aeronautical navigation including localizers, radio ranging and airport control. From 122 to 174 MHz is another general service band for both government and non-government signals. It includes fixed and mobile units and amateur broadcast. Channels 7 through 13 span the frequency range 174-216 MHz. 216-470 MHz includes a number of fixed and mobile communication modes, including some aeronautical navigation and citizens radio. 470-890 MHz includes UHF television channels 14 to 83. Frequencies 890-3000 MHz include a variety of aeronautical and amateur uses, studio-transmitter relays, etc. There are radar bands 1,300-1,600 MHz. VHF电视频道2-4的载波频率覆盖54至72 MHz的频率范围。72-76 MHz之间有一个频段被保留用于政府和非政府服务，包括标准航空信标，频率为75 MHz。VHF电视频道5和6位于76至88 MHz之间。FM广播频段位于VHF电视频道6和7之间，范围是88至108 MHz。FM之上是108-122 MHz的频段，用于航空导航，包括航向台、无线电测距和机场控制。122至174 MHz是另一个通用服务频段，用于政府和非政府信号。它包括固定和移动单元以及业余广播。频道7至13覆盖174-216 MHz的频率范围。216-470 MHz包括多种固定和移动通信模式，包括一些航空导航和公民无线电。470-890 MHz包括UHF电视频道14至83。890-3000 MHz包括多种航空和业余用途，如演播室-发射机中继等。还有雷达频段1，300-1,600 MHz。
The FM stations are assigned center frequencies at 200 kHz separation starting at 88.1 MHz, for a maximum of 100 stations. These FM stations have a 75 kHz maximum deviation from the center frequency, which leaves 25 kHz upper and lower "gaurd bands" to minimize interaction with the adjacent frequency band. Television channels have 5 MHz separation. FM电台的中心频率从88.1 MHz开始，以200 kHz的间隔分配，最多可分配100个电台。这些FM电台的最大频偏为75 kHz，这在上频段和下频段各留出25 kHz的“保护带”，以最小化与相邻频段的干扰。电视频道则有5 MHz的间隔。
The frequency range for mobile cellular telephones is listed as 824.040 - 848.970 MHz. 移动蜂窝电话的频率范围为824.040 - 848.970 MHz。
L-Band for Satellite CommunicationL-Band 用于卫星通信 For example, the Global Positioning System uses two carrier frequencies in this band for broadcasting navigation data.
超高频无线电波段中390-1550 MHz的频段被指定为L波段，用于多种卫星通信目的。例如，全球定位系统使用该波段的两个载波频率来广播导航数据。 |
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Microwaves, Radar微波，雷达
While there are some radar bands from 1,300 to 1,600 MHz, most microwave applications fall in the range 3,000 to 30,000 MHz (3-30 GHz). Current microwave ovens operate at a nominal frequency of 2450 MHz, a band assigned by the FCC. There are also some amateur and radio navigation uses of the 3-30 GHz range. In interactions with matter, microwave radiation primarily acts to produce molecular rotation and torsion, and microwave absorption manifests itself by heat. Molecular structure information can be obtained from the analysis of molecular rotational spectra, the most precise way to determine bond lengths and angles of molecules. Microwave radiation is also used in electron spin resonance spectroscopy. 尽管有部分雷达波段在1300至1600 MHz之间，大多数微波应用集中在3000至30000 MHz（3-30 GHz）范围内。目前微波炉的工作频率为2450 MHz，该频段由FCC分配。此外，3-30 GHz频段也用于业余和无线电导航。在与物质相互作用时，微波辐射主要产生分子旋转和扭转，微波吸收则表现为热量。分子结构信息可通过分析分子旋转光谱获得，这是确定分子键长和键角最精确的方法。微波辐射也用于电子自旋共振光谱学。
For microwave ovens and some radar applications, the microwaves are produced by magnetrons. 对于微波炉和某些雷达应用而言，微波是由磁控管产生的。
Of great astrophysical significance is the 3K background radiation in the universe, which is in the microwave region. It has recently been mapped with great precision by the WMAP probe. 宇宙中具有重大天体物理学意义的是宇宙微波背景辐射，它位于微波波段。该辐射最近已被WMAP探测器以很高精度测绘出来。
Electromagnetic spectrum电磁谱 |
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Millimeter Waves, Telemetry毫米波，遥测
The range 30-300 GHz is used for a variety of experimental, government and amateur purposes in communication.
Electromagnetic spectrum电磁谱 30至300 GHz的频段被用于通信领域的多种实验、政府和业余用途。 |
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