What Are RSSI Range and CSI Wi-Fi? Saving the Changed Value in Wireless - Antenna Alignment

Practice

What is RSSI Range? save the changed value in the item: Wireless - Antenna Alignment in the router or repeater settings

RSSI Range (Received Signal Strength Indication Range) is the range of values indicating the power of the received signal. In wireless communication systems such as Wi-Fi, Bluetooth, Zigbee and others, RSSI is used to estimate the strength of the signal received from a remote device.

The RSSI range represents numerical values, measured in decibels (dBm), indicating the power of the received signal. Typically these values can range from low negative numbers (for example, -100 dBm), which indicates a weak signal, to higher positive numbers (for example, 0 dBm), which indicates a strong signal.

The RSSI range is an important parameter for evaluating the quality of communication in wireless networks. It can be used to determine connection stability, optimize device placement for better signal reception, and other purposes related to wireless communication management.

What Are RSSI Range and CSI Wi-Fi? Saving the Changed Value in Wireless - Antenna Alignment

It cannot be saved.
Users can use the antenna alignment tool to adjust the orientation of their access points by using a signal level meter, with which they can find the best antenna orientation direction.
In other words, you watch what happens if you rotate the antenna.

In other words, in RSSI RANGE you set the desired signal level value. Example, we set up two points facing each other, set the maximum RSSI RANGE value = 55 dB, the reception of the opposite point, say, Remote AP RSSI = 45 dB, the upper Signal percent scale shows 82%. We turn the point right-left, achieving max signal, or the highest percentage. We turn right, the signal dropped from 45 to 40, we go back, i.e. turn left, the signal increased to 50, we turn further, the signal dropped again, we go back to the mark where we caught 50.
And if you set 45, then the Signal percent scale will show 100%.

What is CSI Wi-Fi

CSI Wi-Fi — is a technology for analyzing the state of the wireless channel (Channel State Information), which allows using ordinary Wi-Fi signals not only for data transmission, but also for «sensing» the surrounding environment: tracking the movement of people, breathing, position of objects and even building positioning systems.

CSI (Channel State Information) — is detailed parameters of the Wi-Fi channel: amplitude, phase, signal delay, channel matrix, etc.
Unlike ordinary RSSI (signal level), CSI provides a much more detailed picture of the passage of radio waves.
The Wi-Fi signal is reflected from walls, furniture and people's bodies; analyzing changes in CSI allows you to «see» the movement and state of objects without cameras or sensors.

Depending on the location of the transmitter and receiver, CSI measurement can be classified as bistatic or monostatic.

Bistatic sensing: two devices participate in the sensing process — one sends Wi-Fi signals, and the other receives Wi-Fi signals.
Monostatic sensing: the same device is used for receiving and transmitting Wi-Fi signals. For example, the channel state information (CSI) function provided by Huawei access points innovatively uses joint antenna and algorithm design to minimize non-ideal factors and strong self-interference between the transmitter and receiver. One access point can detect movements in the surrounding environment with centimeter-level accuracy, using capabilities similar to sonar, without the need for other devices. This significantly reduces deployment and maintenance costs.

What Are RSSI Range and CSI Wi-Fi? Saving the Changed Value in Wireless - Antenna Alignment
Bistatic and monostatic sensing

Main applications

Human activity monitoring: walking, breathing, falls — useful for medicine and the «smart home».
Indoor positioning: determining location inside buildings without GPS.
Security: detecting the presence of people in the Wi-Fi coverage area.
Intelligent buildings: automation of lighting, climate control and other systems based on movement.

Technical features

Operates based on the multipath effect: the signal arrives at the antenna via a direct path and through reflections.
CSI captures changes in these paths, which allows analyzing even minor movements.
Modern chips, for example ESP32 from Espressif, support CSI data collection, which makes the technology accessible for DIY projects and research.

Comparison of CSI and RSSI

Parameter	RSSI (ordinary Wi-Fi)	CSI Wi-Fi
Detail	Signal level only	Amplitude, phase, delay, channel matrix
Application	Determining communication quality	Positioning, activity monitoring
Accuracy	Low	High (can capture breathing)
Equipment	Any Wi-Fi adapter	Special chips (ESP32, Intel 5300)