Question

1. Insight into RF systems

a. Would a high-gain dish antenna be suitable for use as the antenna at the base station in a PtMP (Point to Multi-Point) setup, yes or no? Explain your answer.

2. Radio frequency terminology:

Research and concisely describe the following RF terms:

1. Isotropic antenna
2. Antenna gain
3. Beam width

Answer 1

(1) Would a high-gain dish antenna be suitable for use as the antenna at the base station in a PtMP (Point to Multi-Point) setup:

Answer: Yes

Explanation:

Using High gain dish antenna at base station in PtMP - Point to Multi-point setup provides antenna reciprocity and gives better network performance. High gain dish antenna can have more focused beam width and greater propagation capabilities.

Example:

● As shown in above scenario, Customer A and Customer B are close to Base Station access point. These two has excellent signal strength through their 16dBi antennas. Customer C is at greater distance from the Base Station access point. This is getting weaker signal and it has also 16dBi antenna.

● More time will be spent on customer C for retransmissions in time based Point-to-Multipoint solutions. Increasing the output power of the Access Point or Customer C will result increase in noise and interference. That will give decrease in the network performance.

● Solution for this is to use higher gain dish antenna. High gain dish antenna has more focused and controlled beam width and greater and effective propagation capabilities. To spent less time on Customer C in retransmissions, increase the gain of C.

● That will result positive increase in network performance. This Point to Multipoint solutions is also known as Antenna Reciprocity.

(2) Research and concisely describe the following RF terms:

(1) Isotropic antenna

An isotropic antenna emits or radiates the signal equally and uniformly in all directions i.e. in horizontal and vertical directions with the same intensity.

It is also known as omnidirectional antenna. The transmitted signal power is the same or equal at distance d from the antenna in various directions.

(2) Antenna gain

Antenna gain is the ability measure of the antenna to effectively transmit or radiate more or less in any specific direction compared to an isotropic source or theoretical antenna. The dBi or dBd are decibels measures of antenna gain.

(3) Beam Width

The antenna beam width is a unit or measure of the angular scale extent of the most powerful part or portion of the radiated energy. This evaluates the expected signal strength in the particular direction and measures the radiation distance of an antenna.