EYE FAQ - Revision history

Vytenis.kibildis: /* Can dBm (RSSI) be converted to distance in meters? */

2026-03-05T08:44:31Z

Can dBm (RSSI) be converted to distance in meters?

← Older revision		Revision as of 11:44, 5 March 2026
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	Source: https://wiki.teltonika-gps.com/view/EYE_BEACON_/_BTSID1#EYE_Beacon_Protocol_overview		Source: https://wiki.teltonika-gps.com/view/EYE_BEACON_/_BTSID1#EYE_Beacon_Protocol_overview
	==== Can dBm (RSSI) be converted to distance in meters? ====		==== Can dBm (RSSI) be converted to distance in meters? ====
	~~Yes —~~ RSSI (signal strength measured in dBm) can be used to estimate the distance between a BLE beacon and a scanner. However, ~~the value should be treated as~~ an approximation rather than an exact measurement.		RSSI (signal strength measured in dBm) can be used to estimate the distance between a BLE beacon and a scanner. However, this is always an approximation rather than an exact measurement.
	RSSI ~~represents received signal power at the scanner antenna~~. ~~As radio signals travel through space they weaken~~, ~~which allows systems to estimate~~ distance ~~using radio propagation models~~. ~~The most commonly used approach is~~ the ~~log-distance path loss model, which compares~~ the measured RSSI value with the expected signal strength at a reference distance (~~typically~~ 1 meter).
			There is no universal calculator or Excel sheet that can accurately convert RSSI (dBm) to meters for all deployments. RSSI-based distance estimation depends on environment, installation conditions, device orientation, hardware differences, and configuration parameters.

			Because of this, distance can usually only be roughly estimated and should ideally be validated with measurements in the specific installation environment.

			How the estimation works:
			BLE systems compare the measured RSSI value with the expected signal strength at a reference distance (usually 1 meter). This approach is commonly known as the log-distance path loss model.

	Example formula used for estimation:		Example formula used for estimation:
	distance = 10 ^ ((TxPower - RSSI) / (10 × n))		distance = 10 ^ ((TxPower - RSSI) / (10 × n))

	Where:		Where:
	TxPower – expected RSSI at 1 meter from the beacon		TxPower – expected RSSI at 1 meter from the beacon
	RSSI – measured signal strength at the scanner		RSSI – measured signal strength at the scanner
	n – environment factor (path-loss exponent)		n – environment factor (path-loss exponent)
	Typical values for n:
			Typical environment values for n:
	Free space: 2		Free space: 2
	Office environment: 2.7–3		Office environment: 2.7–3
	Warehouse: 3–4		Warehouse: 3–4
	Industrial environments: 4–5		Industrial environments: 4–5
	~~Because indoor environments contain walls, metal structures, people, and signal reflections, the calculated~~ distance ~~may vary significantly. For this reason RSSI is most reliable for proximity estimation rather than precise ranging~~.
	Typical indoor approximation:		Example calculation:
			TxPower @ 1 m = -59 dBm
			Measured RSSI = -70 dBm
			Environment factor n = 2.7
			Estimated distance ≈ 3.4 meters

			Typical indoor RSSI approximation:
	-50 dBm ≈ ~1 m		-50 dBm ≈ ~1 m
	-60 dBm ≈ 1–2 m		-60 dBm ≈ 1–2 m
	-70 dBm ≈ 2–5 m		-70 dBm ≈ 2–5 m
	-80 dBm ≈ 5–10 m		-80 dBm ≈ 5–10 m
	~~Due~~ to ~~environmental~~ factors, RSSI~~-based~~ distance ~~estimation in indoor environments may vary by several meters~~.
	The EYE application uses an RSSI-based estimation model similar to the formula above~~, therefore the~~ displayed distance should be interpreted as an approximate proximity indicator rather than an exact physical distance.		These values are approximate and can vary significantly indoors due to walls, metal structures, people, signal reflections, antenna orientation, and scanner hardware differences.

			Because of these factors, RSSI is most reliable for proximity estimation (near / far detection) rather than precise distance measurement.

			The Teltonika EYE application uses an RSSI-based estimation model similar to the formula above. The displayed distance should therefore be interpreted as an approximate proximity indicator rather than an exact physical distance.

	==== What data can be read from the accelerometer? ====		==== What data can be read from the accelerometer? ====

Vytenis.kibildis: /* Is it possible to receive the RSSI value from the sensor/ID? */

2026-03-05T08:40:21Z

Is it possible to receive the RSSI value from the sensor/ID?

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 ==== Is it possible to receive the RSSI value from the sensor/ID? ====
   Yes, both send RSSI voltage in the Eddystone/iBeacon protocol part.
   Source: https://wiki.teltonika-gps.com/view/EYE_BEACON_/_BTSID1#EYE_Beacon_Protocol_overview
 ==== What data can be read from the accelerometer? ====

Vytenis.kibildis: /* Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? */

2026-02-06T07:25:07Z

Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device?

← Older revision		Revision as of 10:25, 6 February 2026
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	==== Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? ====		==== Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? ====
	Some CR2450 battery datasheets list -40°C as the minimum operating temperature, but this does not mean the battery can reliably power a device at that temperature. The -40°C rating is often measured under no-load or minimal-load conditions (i.e., the battery is not actively powering a device). Meaning the datasheet temperature range simply indicates the extreme limits where the battery won’t physically fail, but it does not guarantee usable performance for our or any similar devices.		Some CR2450 battery datasheets list -40°C as the minimum operating temperature, but this does not mean the battery can reliably power a device at that temperature. The -40°C rating is often measured under no-load or minimal-load conditions (i.e., the battery is not actively powering a device). Meaning the datasheet temperature range simply indicates the extreme limits where the battery won’t physically fail, but it does not guarantee usable performance for our or any similar devices.

	==== What is the direction of EYE Senor's or Beacon's antenna? ====		==== What is the direction of EYE Senor's or Beacon's antenna? ====

Vytenis.kibildis: /* What Happens to a CR2450 Battery at -40°C? */

2026-02-06T07:24:49Z

What Happens to a CR2450 Battery at -40°C?

← Older revision		Revision as of 10:24, 6 February 2026
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	==== What Happens to a CR2450 Battery at -40°C? ====		==== What Happens to a CR2450 Battery at -40°C? ====
	At -40°C, the CR2450 battery experiences severe performance issues due to extreme cold affecting its chemical processes. The electrolyte thickens, slowing down ion movement, which leads to voltage drops, rapid capacity loss, and unstable operation. In many cases, the battery cannot provide enough power, causing the device to shut down or fail to function properly. Unlike industrial-grade lithium batteries, the CR2450 is not designed for continuous operation in such extreme conditions.		At -40°C, the CR2450 battery experiences severe performance issues due to extreme cold affecting its chemical processes. The electrolyte thickens, slowing down ion movement, which leads to voltage drops, rapid capacity loss, and unstable operation. In many cases, the battery cannot provide enough power, causing the device to shut down or fail to function properly. Unlike industrial-grade lithium batteries, the CR2450 is not designed for continuous operation in such extreme conditions.

	==== Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? ====		==== Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? ====
	Some CR2450 battery datasheets list -40°C as the minimum operating temperature, but this does not mean the battery can reliably power a device at that temperature. The -40°C rating is often measured under no-load or minimal-load conditions (i.e., the battery is not actively powering a device). Meaning the datasheet temperature range simply indicates the extreme limits where the battery won’t physically fail, but it does not guarantee usable performance for our or any similar devices.		Some CR2450 battery datasheets list -40°C as the minimum operating temperature, but this does not mean the battery can reliably power a device at that temperature. The -40°C rating is often measured under no-load or minimal-load conditions (i.e., the battery is not actively powering a device). Meaning the datasheet temperature range simply indicates the extreme limits where the battery won’t physically fail, but it does not guarantee usable performance for our or any similar devices.

Vytenis.kibildis: /* Voltage drop in low temperatures */

2026-02-06T07:24:33Z

Voltage drop in low temperatures

← Older revision		Revision as of 10:24, 6 February 2026
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	A voltage drop with decreasing temperature is an expected physical effect in batteries. Devices should not shut down solely due to temperature-driven voltage variation unless there are underlying issues or the temperature is outside the specified operating range.		A voltage drop with decreasing temperature is an expected physical effect in batteries. Devices should not shut down solely due to temperature-driven voltage variation unless there are underlying issues or the temperature is outside the specified operating range.

	Battery voltage can therefore be interpreted as a temperature-dependent indicator when estimating performance~~. For example, a reading of 2.7 V at room temperature might correspond to ~30% remaining capacity, whereas at −10 °C the same 2.7 V could still indicate a nearly full battery~~.		Battery voltage can therefore be interpreted as a temperature-dependent indicator when estimating performance.

	==== What Happens to a CR2450 Battery at -40°C? ====		==== What Happens to a CR2450 Battery at -40°C? ====
	At -40°C, the CR2450 battery experiences severe performance issues due to extreme cold affecting its chemical processes. The electrolyte thickens, slowing down ion movement, which leads to voltage drops, rapid capacity loss, and unstable operation. In many cases, the battery cannot provide enough power, causing the device to shut down or fail to function properly. Unlike industrial-grade lithium batteries, the CR2450 is not designed for continuous operation in such extreme conditions.		At -40°C, the CR2450 battery experiences severe performance issues due to extreme cold affecting its chemical processes. The electrolyte thickens, slowing down ion movement, which leads to voltage drops, rapid capacity loss, and unstable operation. In many cases, the battery cannot provide enough power, causing the device to shut down or fail to function properly. Unlike industrial-grade lithium batteries, the CR2450 is not designed for continuous operation in such extreme conditions.

Vytenis.kibildis: /* Voltage drop in low temperature Temperature */

2026-02-06T07:23:26Z

Voltage drop in low temperature Temperature

← Older revision		Revision as of 10:23, 6 February 2026
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	CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year		CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year

	==== Voltage drop in low ~~temperature Temperature~~ ====		==== Voltage drop in low temperatures ====
	~~Battery~~ voltage ~~and capacity~~ drop ~~due to~~ temperature is expected ~~physics reaction~~.		A voltage drop with decreasing temperature is an expected physical effect in batteries. Devices should not shut down solely due to temperature-driven voltage variation unless there are underlying issues or the temperature is outside the specified operating range.
	Devices should not ~~turn off or die~~ due to variation ~~in temperature~~ unless ~~they already had problems due to other factors~~ or the ~~temperatures are~~ outside of the operating range.
	~~Voltage~~ can be ~~used~~ as a temperature-dependent indicator ~~for~~ estimating performance.		Battery voltage can therefore be interpreted as a temperature-dependent indicator when estimating performance. For example, a reading of 2.7 V at room temperature might correspond to ~30% remaining capacity, whereas at −10 °C the same 2.7 V could still indicate a nearly full battery.
	For example:
	~~A battery at~~ 2.~~7V in~~ room temperature ~~may still have~~ 30% capacity,
	~~But~~ at ~~-10°C,~~ the same 2.~~7V may mean the battery is~~ nearly full.

	==== What Happens to a CR2450 Battery at -40°C? ====		==== What Happens to a CR2450 Battery at -40°C? ====

Vytenis.kibildis at 07:21, 6 February 2026

2026-02-06T07:21:41Z

← Older revision		Revision as of 10:21, 6 February 2026
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	3.2 – 2.8 V → excellent		3.2 – 2.8 V → excellent
	2.8 – 2.5 V → working range		2.8 – 2.5 V → working range
	2.5 – ~~2.2 V → start monitoring~~		2.5 – 2.2 V → low (approx. 10–15% remaining) start monitoring
	2.2 V → low (approx. 10–15% remaining)
	2.0V → depleted		2.0V → depleted
	==== How does the battery voltage translate into the percentage of the battery? ====		==== How does the battery voltage translate into the percentage of the battery? ====
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	==== What is the battery chemistry used in beacons/sensors and what is the self-discharge rate of these batteries? ====		==== What is the battery chemistry used in beacons/sensors and what is the self-discharge rate of these batteries? ====
	CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year		CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year

			==== Voltage drop in low temperature Temperature ====
			Battery voltage and capacity drop due to temperature is expected physics reaction.
			Devices should not turn off or die due to variation in temperature unless they already had problems due to other factors or the temperatures are outside of the operating range.
			Voltage can be used as a temperature-dependent indicator for estimating performance.
			For example:
			A battery at 2.7V in room temperature may still have 30% capacity,
			But at -10°C, the same 2.7V may mean the battery is nearly full.

			==== What Happens to a CR2450 Battery at -40°C? ====
			At -40°C, the CR2450 battery experiences severe performance issues due to extreme cold affecting its chemical processes. The electrolyte thickens, slowing down ion movement, which leads to voltage drops, rapid capacity loss, and unstable operation. In many cases, the battery cannot provide enough power, causing the device to shut down or fail to function properly. Unlike industrial-grade lithium batteries, the CR2450 is not designed for continuous operation in such extreme conditions.

			==== Why -40°C in the Datasheet Doesn’t Mean the Battery Can Power the Device? ====
			Some CR2450 battery datasheets list -40°C as the minimum operating temperature, but this does not mean the battery can reliably power a device at that temperature. The -40°C rating is often measured under no-load or minimal-load conditions (i.e., the battery is not actively powering a device). Meaning the datasheet temperature range simply indicates the extreme limits where the battery won’t physically fail, but it does not guarantee usable performance for our or any similar devices.

	==== What is the direction of EYE Senor's or Beacon's antenna? ====		==== What is the direction of EYE Senor's or Beacon's antenna? ====
	BTS Beacon/Sensor antenna is unidirectional. Antenna signal strength is very similar in all directions.		BTS Beacon/Sensor antenna is unidirectional. Antenna signal strength is very similar in all directions.
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	==== What is the BLE transmission range of BTS devices? ====		==== What is the BLE transmission range of BTS devices? ====
	According to the tests done by us using FMB1YX trackers: the detection range in an open field in real conditions for the EYE Beacon/Sensor was 80 to 100m. Take note that the maximum range will also depend on the quality of the receiving device antenna.		According to the tests done by us using FMB1YX trackers: the detection range in an open field in real conditions for the EYE Beacon/Sensor was 80 to 100m. Take note that the maximum range will also depend on the quality of the receiving device antenna.


	===<big>Questions about EYE Accessory configuration (EYE APP)</big>===		===<big>Questions about EYE Accessory configuration (EYE APP)</big>===

Vytenis.kibildis: /* How does the battery voltage translate into the percentage of the battery? */

2026-02-06T07:13:06Z

How does the battery voltage translate into the percentage of the battery?

← Older revision		Revision as of 10:13, 6 February 2026
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	2.0V → depleted		2.0V → depleted
	==== How does the battery voltage translate into the percentage of the battery? ====		==== How does the battery voltage translate into the percentage of the battery? ====
	At the ~~moment~~ voltage is ~~not~~ directly translated into percentage as the voltage varies depending on the temperature sensor is in. We are working on battery life tests depending on temperature and various advertising frequencies and signal strength and we will be evaluating the possibility to ~~send battery~~ percentage ~~in the future once those tests are done. For now~~, ~~you can refer to the graph from~~ the battery ~~datasheet~~ for a ~~rough estimation of~~ the remaining ~~battery life~~.		Battery discharge does not follow a linear pattern; it follows a curve. For most of the battery’s usable life, the voltage remains relatively stable, then declines rapidly near end-of-life. If voltage is mapped directly to a percentage, the battery would appear to stay around 80–100% for a long time and then drop to 0% quickly, which misrepresents the actual remaining capacity and leads to misleading state-of-charge estimates.
	[[File:Battery lifetime datasheet.png\|frameless\|454x454px]]		[[File:Battery lifetime datasheet.png\|frameless\|454x454px]]

	==== What is the battery chemistry used in beacons/sensors and what is the self-discharge rate of these batteries? ====		==== What is the battery chemistry used in beacons/sensors and what is the self-discharge rate of these batteries? ====
	CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year		CR2450 Lithium, Manganese Dioxide(MnO2), Self-discharge 1% per 1 year

Vytenis.kibildis at 07:11, 6 February 2026

2026-02-06T07:11:00Z

← Older revision		Revision as of 10:11, 6 February 2026
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	==== What is battery voltage when the battery is considered empty? ====		==== What is battery voltage when the battery is considered empty? ====
	~~Around~~ 2.~~2V is when the device's battery is~~ low ~~and around~~ 2.0V ~~battery can be considered~~ depleted.		3.2 – 2.8 V → excellent
			2.8 – 2.5 V → working range
			2.5 – 2.2 V → start monitoring
			2.2 V → low (approx. 10–15% remaining)
			2.0V → depleted
	==== How does the battery voltage translate into the percentage of the battery? ====		==== How does the battery voltage translate into the percentage of the battery? ====
	At the moment voltage is not directly translated into percentage as the voltage varies depending on the temperature sensor is in. We are working on battery life tests depending on temperature and various advertising frequencies and signal strength and we will be evaluating the possibility to send battery percentage in the future once those tests are done. For now, you can refer to the graph from the battery datasheet for a rough estimation of the remaining battery life.		At the moment voltage is not directly translated into percentage as the voltage varies depending on the temperature sensor is in. We are working on battery life tests depending on temperature and various advertising frequencies and signal strength and we will be evaluating the possibility to send battery percentage in the future once those tests are done. For now, you can refer to the graph from the battery datasheet for a rough estimation of the remaining battery life.

Vytenis.kibildis at 05:17, 9 September 2025

2025-09-09T05:17:27Z

← Older revision		Revision as of 08:17, 9 September 2025
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	==== Are individual calibration certificates available? ====		==== Are individual calibration certificates available? ====
	Yes, see examples attached.		Yes, see examples attached.
	[[File:Calib certificate example 1.png\|frameless]][[File:Calib certificate example 3.png\|frameless]]		[[File:Calib certificate example 1.png\|frameless]][[File:Calib certificate example 2.png\|frameless]][[File:Calib certificate example 3.png\|frameless]]
	==== Do you need to recalibrate the sensors? ====		==== Do you need to recalibrate the sensors? ====