Whether a higher or lower dBm (deciBel-milliwatts) value is better depends on the context of the application and what you are trying to achieve.
In this post we review different signal transmission and reception scenarios and explain situations where higher or lower dBm are better or worse.
Table of Contents
What is dBm?
dBm is a unit of power measurement. It expresses the power level in decibels (dB) relative to 1 mW. It is used to measure the absolute power levels of RF signals, audio signals, and other types of electronic signals.
Where is Higher dBm Better?
When transmitting
Wireless Communication: Higher dBm values indicate higher transmit power, which can result in a stronger signal that can travel longer distances and penetrate obstacles better. This is beneficial for achieving a wider coverage area and stronger connectivity.
Broadcasting: For radio and TV transmitters, a higher dBm value means a stronger broadcast signal, which can cover a larger audience area.
What are the advantages of higher dBm?
Extended Range: Higher power can cover more extensive areas.
Better Signal Penetration: Stronger signals can penetrate buildings and other obstructions more effectively.
What are the disadvantages of higher dBm?
Increased Power Consumption: Higher power levels require more energy, which can reduce battery life in portable devices.
Interference: Higher power can cause interference with other devices and services, particularly in crowded spectrum environments.
Where is Lower dBm Better?
Receive Sensitivity
Wireless Receivers: In the context of receiver sensitivity, lower (more negative) dBm values indicate better sensitivity. A receiver with a sensitivity of -120 dBm is better than one with -100 dBm, as it can detect weaker signals.
Transmit Power
Battery Life: Lower dBm values mean lower transmit power, which can extend battery life in portable and mobile devices.
Reduced Interference: Lower output power levels reduce the risk of causing interference with other devices.
What are the advantages of Lower dBm?
Energy Efficiency: Lower power consumption is critical for battery-operated devices.
Minimal Interference: Lower transmit power reduces the likelihood of interference with other devices.
What are the disadvantages of Lower dBm?
Limited Range: Lower output power levels may result in reduced range and weaker signals, especially in obstructed environments.
Summary
- Higher dBm: Better for transmission over long distances and through obstacles, but at the cost of higher power consumption and potential interference.
- Lower dBm: Better for energy efficiency, sensitivity and reducing interference, but at the cost of range and signal strength.
In conclusion, whether higher or lower dBm values are better depends on the specific requirements and constraints of your application. Understanding the trade-offs involved will help you make the best decision for your particular use case.