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Wireless Transmission Frequencies Radio is a general term for frequencies in the range of 3khz to 300GHz. The properties of radio waves are frequency dependent 30MHz to 1gHz Suitable for omnidirectional applications E. g, broadcast radio 1GHz to 40GHz Referred to as microwave frequencies Can be highly directional Suitable for point-to-point transmission Microwave is also used for satellite communications 3x 10 Hz to 2 x 1014 Hz Infrared Local applications, such as in a single room There are national and international agreements about who gets to use which frequencies AM Fm radio, television, mobile phones, telephone companies, police, maritime navigation, military, government, etc ISM band(Industrial, Scientific, Medical ): unlicensed usage E.g., Cordless phone, radio-controlled toys, bluetooth, wireless LAN 1313 Wireless Transmission Frequencies • Radio is a general term for frequencies in the range of 3kHz to 300GHz. The properties of radio waves are frequency dependent. • 30MHz to 1GHz — Suitable for omnidirectional applications — E.g., broadcast radio • 1GHz to 40GHz — Referred to as microwave frequencies — Can be highly directional — Suitable for point-to-point transmission — Microwave is also used for satellite communications • 3 x 1011 Hz to 2 x 1014 Hz — Infrared — Local applications, such as in a single room • There are national and international agreements about who gets to use which frequencies. — AM & FM radio, television, mobile phones, telephone companies, police, maritime, navigation, military, government, etc. — ISM band (Industrial, Scientific, Medical): unlicensed usage • E.g., Cordless phone, radio-controlled toys, bluetooth, wireless LAN
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