RSSI or Received Signal Strength Indicator is a relative index used to measure the power level in the receiving radio signal after the possible transmission losses. In other words, RSSI measures the power of the received signal at a device. Higher the RSSI value the better is the signal strength. In simple RSSI is a measurement that helps us to determine the quality of WiFi signals perceived at the receiver end.
An RSSI value of -50 dB is always considered excellent for a WiFi network. An RSSI value of -90 represents a poor or unusable signal. This blog post further explores various ways of improving RSSI and WiFi signals
RSSI is measured with values assigned by IEEE 802.11 ranging between 0 to -100Dbm. The higher the value of RSSI the stronger the signal perceived. The following table depicts how RSSI value is related to the quality percentage.
| Quality | Percentage Representation | dBm |
| High | 90%~= | -55 dB |
| Medium | 75%~= | -75 dB |
| Low | 30%~= | -85 dB |
| Unusable/Poor | 8%~= | -96 dB |
RSSI Vs dBm: A Comparison
RSSI and dBm (decibel milliwatts) are different units of measurement but both are used to measure signal strength. The main difference between these two measurements is: RSSI is a relative index and dBm is an absolute unit of measurement. Further dBm measurement is done using milliwatts (mW).
The IEEE 802.11 standard allows WiFi manufacturers to have the RSSI value range between 0 to 255. Allowing each of the manufacturers to have their own RSSI_Maximum value defined. For instance, Cisco has RSSI values set between 0 to 100 and another manufacturer Atheros has a range fixed between 0 to 60. Higher the RSSI value better is the signal strength and closer the dBm to 0 better is the signal strength.
Reasons for Bad RSSI levels
The RSSI measurement might indicate low signal levels due to many reasons. An important one amongst them is Interference. Interference can lead to poor quality signals, setup failures, and frequently dropped connections.
Usually, an RSSI value lower than -80 dBm is considered poor signal strength. Some clients mark the RSSI value of -75 dBm as poor signal strength. In a nutshell, we can consider any values in the range of -70 dBm to -80 dBm as unacceptable.
How to measure RSSI Signal:
RSSI value can be determined in Windows, Mac and Linux systems by following the simple steps given below:
Windows System:
In the Windows system, you can employ WifiInfoView a free application to determine the RSSI of all networks detected by your computer.
Mac System:
- Use Option-click the Wi-Fi menu.
- Further determine the RSSI for, your current connection
Linux System:
- Enter the command iwconfig in the command line
Use the wireless adapter section to determine the RSSI Signal value
Tips to Improve WiFi Signal strength
WiFi signal varies from one location to another within your home. Ensuring a uniformly available WiFi signal strength within the home is sometimes a challenging task. Sometimes, the WiFi signal strength can drastically diminish by just moving a single step either to the left or right. Various factors like physical distance, obstructions, interference, router capabilities, bandwidth hoggers, quality of internet service provider, and absence of performance enhancement features in your routers contribute to poor WiFi signals. Here is a brief description of how the aforementioned factors affect WiFi signal strength:
Physical distance: The WiFi routers do not transmit as powerfully as cell towers. The reason is safety and security issues. Particularly cheap routers struggle to even cover a small apartment effectively. Repositioning WiFi routers in a strategic way through experimentation and minimizing the distance between receiving devices and the router helps to address the hindrance of physical distance.
Buy a long range router to cover the entire home In case if you have bad signal reception at some places of your home. read this article for more information on Long range wifi routers.
Obstructions: WiFi signals get partially absorbed or even blocked by various furniture and walls present in a house. Particularly, 5GHz WiFi signal is more vulnerable to obstructions caused by household articles.
Interference: WiFi signals of your apparatus can get interference from WiFi signals of neighbours in case you reside in apartments. Also, signals from cell phones, baby monitors, walkie-talkies can also interfere with your WiFi devices.
Limited Power of Routers: Many Routers come with limited capabilities. It is impossible for a limited capability router to support dozens of devices at home or office environment.
Bandwidth Hoggers: Streaming on multiple devices and video chatting can make the internet crawl even with good WiFi signal strength. So bandwidth stealing hoggers are one of the culprits slowing down the WiFi network.
We have a great content on how to choose router for data hoggers like gaming devices, check this article – gaming routers for gamers.
Internet Service Provider to be blamed: Often the ISP promises a different speed and delivers something else. So, it is necessary to test internet speed and take appropriate action against the ISPs.
Lack of Performance Enhancing Features: Old Routers do not have the performance enhancement capabilities and Quality of Service, Multi-user MIMO (MU-MIMO), beamforming features etc. This acts as a bottleneck in ensuring better WiFi signals.
Having discussed various bottlenecks for WiFi signals. Let us now concentrate on the measures that help to boost or improve WiFi signals.
Strategical Placement of the Router: Almost all appliances in a house emit electromagnetic waves and the biggest culprit blocking WiFi signals is Metal enclosures or metal particles. Avoid placing Routers next to metal appliances as they create a dead zone. Also, Appliances like washing machines, televisions, tumble dryers, cordless phones interfere with WiFi signals. Materials like wood, glass, foam, plastics, cardboards also cause disruptions to WiFi signals but with less severity.
Keep Routers Updated: Malware attacks are common today. Often this malware slows down the Routers by injecting malicious code into the system. The best rule of thumb is to keep updating the Router software and ensure it is not infected by malware. Once a Router is affected by malware it spreads across the network to other devices.
Secure WiFi with Strong Passwords: Do not think that your neighbors will not cling to your WiFi connection. With a hunger for WiFi usage growing day by day anyone can start using your WiFi network. So, ensure you provide cryptic, strong not easy to guess passwords to your WiFi devices.
Invest in a WiFi Repeater/Booster/Extender:
Though the terms Repeaters, Boosters, and Extenders are used interchangeably and all of them help to strengthen the WiFi signals they are technically different.
The WiFi Repeaters just rebroadcast the original signal in the form of an extension of the original network.
The WiFi Boosters and Extenders amplify the original signal before rebroadcasting and thus enhance the signal strength. While WiFi Boosters have a greater range than WiFi Extenders they are preferred in the places where the signal is weak.
Utilize Different WiFi Channels:
The majority of us get stuck to default settings when using any gadgets or applications. Similar to National Highways WiFi also has multiple lanes or channels.
The 2.4 GHz frequency band has 11 WiFi Channels and the 5 GHz has frequency band has 45 WiFi Channels. Among the many users who set their router to work in default channels 1 and 6 respectively. Instead of congesting yourselves by sticking to default channels exploring other channels offers better signal strength.
Conclusion
RSSI helps you to measure how well a receiving device can hear a signal coming from the transmitter or Access Point. RSSI is a relative index ranging between 0 to 255. Higher the value better the signal strength. Whenever the WiFi signal is strong and still the quality of service is poor blame it on Interference. The WiFi interferers can be handled with WiFi adapters but In order to find out Non-WiFi interferers, you have to rely on spectrum analysis tools.