What is microwave?

What is microwave?

Microwave is a kind of electromagnetic wave. In a broad sense, the frequency range of microwave is 300 MHz to 300 GHz. In microwave communication, the frequency range generally is from 3 GHz to 30 GHz. According to the characteristics of microwave propagation, microwave can be considered as plane wave. The plane wave has no electric field and magnetic field longitudinal components along the propagation direction. The electric field and magnetic field components are vertical to the propagation direction. Therefore, it is called “transverse electromagnetic wave” or TEM for short.

lWhat is digital microwave communication? Digital microwave communication is a way of transmitting digital information in atmosphere on microwave or radio frequency (RF). It adopts the digital modulation scheme. The baseband signal is processed in the Intermediate Frequency (IF) unit. Then the signal is converted into the microwave frequency band through frequency conversion.

What frequency bands are commonly used in digital microwave communication?

According to ITU-R Recommendations, the common frequency bands include 7G/8G/11G/13G/15G/18G/23G/26G/32G/38G. Higher or lower bands may also be employed     along with the development of technologies but the application is rare. Different bands are applied to different fields.

What concepts are involved in microwave frequency setting?

  The concepts include central frequency, transmit/receive spacing, channel spacing and protection spacing.

What are the frequently used modulation schemes? Which are the most frequently-used?

  The frequently-used modulation modes are ASK, FSK, PSK and QAM. The most frequently-used are PSK and QAM.