Microwave Communication: Advantages and Disadvantages

This page discusses the pros and cons of microwave communication.

Frequencies ranging from 1 GHz to 30 GHz are classified as Microwaves. These microwave frequencies have wavelengths measured in centimeters. The microwave band is further divided into UHF, SHF, EHF, and others. It occupies the upper portion of the radio frequency spectrum.

Advantages of Microwave Communication

Here are the benefits of using microwave communication:

• Large Bandwidth: The microwave spectrum offers a wider bandwidth, enabling the transmission of a larger amount of information.

• Spectrum Management: With the increasing congestion of the radio frequency spectrum, microwave technology provides solutions through the use of highly selective receivers, advanced modulation techniques (SSB, PSK, QAM, etc.), spread spectrum techniques, and data compression.

• Channel Allocation: The microwave spectrum is divided into different channels based on specific applications. The center frequencies for these channels are carefully allocated with gaps to prevent overlapping and interference between adjacent channels.

• Line of Sight Communication: Microwave communication has long been used as a Line of Sight (LOS) communication method, particularly in hilly and remote areas where wired communication infrastructure is difficult to install. Microwave and satellite communications are excellent choices for these locations.

Disadvantages of Microwave Communication

As useful as microwaves are for communication, there are also some drawbacks:

• Complex Circuit Analysis: Unlike frequencies below 30 MHz where standard circuit analysis applies, microwave frequencies require E-H wave analysis, adding complexity to the design and analysis process.

• Component Limitations: Traditional lumped components like resistors, inductors, and capacitors exhibit different characteristics at microwave frequencies compared to their behavior at lower frequencies. This makes implementing these components challenging in microwave circuits.

• Transit Time Issues: At microwave frequencies, the transit time of current carriers (electrons) is significant, representing a substantial portion of the signal period. Consequently, conventional transistors may not perform optimally at microwave frequencies compared to lower frequencies.

• Line of Sight Restriction: Microwave communication is limited to line-of-sight propagation. This means that communication is only possible if there is a clear, unobstructed path between the transmitting and receiving antennas. Other communication modes are not possible.