LoRa Link Budget Calculator

A LoRa Link Budget Calculator helps estimate whether a LoRa wireless link has enough RF power to maintain communication between a transmitter and receiver. Instead of looking only at distance, a link-budget calculation considers transmit power, antenna gain, cable losses, path loss, receiver sensitivity, spreading factor, bandwidth, and receiver noise figure.

This engineering version calculates several important RF parameters, including receiver sensitivity, TX EIRP, expected received power (RSSI), maximum allowable path loss (MAPL), link margin, and the LoRa demodulator SNR limit.

The core idea is straightforward: calculate how much signal reaches the receiver, determine how weak a signal the receiver can theoretically demodulate, and compare the two.

A positive link margin means the predicted received signal is above the calculated sensitivity. A negative margin means the predicted signal is below the sensitivity threshold and the link is expected to fail under the assumptions entered into the calculator.

How Does a LoRa Link Budget Calculator Work?

A LoRa link budget accounts for the RF power available at the transmitter, gains introduced by the antennas, losses in cables and connectors, attenuation through the propagation path, and the receiver's sensitivity.

The calculator first estimates receiver sensitivity using bandwidth, receiver noise figure, and the SF-specific demodulator SNR limit. It then calculates TX EIRP and expected received power. Finally, it compares received power with sensitivity to determine the link margin.

The primary link-budget relationship is:

Link Margin = P_tx − L_ct + G_tx − PL + G_rx − L_cr − S_rx

Where:

• P_tx = transmitter output power in dBm
• G_tx = transmitter antenna gain in dBi
• G_rx = receiver antenna gain in dBi
• L_ct / L_cr = cable and connector losses
• PL = propagation path loss in dB
• S_rx = receiver sensitivity in dBm

The larger the positive margin, the more theoretical headroom the link has against additional attenuation. However, a calculator result should not be interpreted as a guarantee of real-world coverage.

What Is a LoRa Link Budget?

A LoRa link budget is an accounting of the RF gains and losses between a LoRa transmitter and receiver. It determines whether enough signal power should remain at the receiver for successful demodulation.

For example, a LoRa sensor may transmit at 14 dBm, but the signal does not arrive at the gateway at 14 dBm. Antenna characteristics can increase effective radiated power, while coaxial cables, connectors, free-space propagation, buildings, vegetation, terrain, and other environmental factors can reduce the signal substantially.

The receiver also has a minimum signal requirement. That requirement is represented by receiver sensitivity.

A basic link-budget workflow is therefore:

Transmitter power → antenna/cable effects → propagation loss → receiver antenna/cable effects → received power → sensitivity comparison

This is why distance by itself is not enough to determine whether a LoRa connection will work.

Two LoRa devices separated by the same physical distance can have very different link performance if one link has clear line of sight while another passes through buildings, dense vegetation, or difficult terrain.

Link Budget vs. Distance

A link budget is fundamentally a power calculation, not simply a distance calculation.

Distance can influence path loss, but path loss also depends on factors such as operating frequency and the propagation environment. For preliminary engineering, the calculator is most useful when you have an estimated or measured path loss and want to determine how much link margin remains.

LoRa Link Budget Calculator Inputs

The calculator uses eight primary inputs. Each represents an important part of the RF link.

TX Output Power

TX Output Power (P_tx) is the RF power produced by the transmitter, expressed in dBm.

The calculator allows values from −10 to 30 dBm.

For example, a transmitter configured for 14 dBm produces approximately 25 mW of RF power.

Increasing transmitter power can increase the available link budget, but it is not automatically the best way to solve a weak link. Regulatory limits, power consumption, interference, and antenna characteristics must also be considered.

For an engineering calculation, use the actual configured or measured RF output power rather than assuming the maximum value supported by the radio.

TX Antenna Gain

TX Antenna Gain (G_tx) represents the transmitter antenna's gain in dBi.

Antenna gain affects how effectively the available RF power is directed. The calculator adds TX antenna gain when calculating EIRP.

For example, with:

• TX power = 14 dBm
• TX antenna gain = 2.15 dBi

the antenna system has a higher effective radiated level than the transmitter output alone.

Actual antenna performance can differ from nominal specifications because of installation conditions, frequency, orientation, impedance matching, nearby objects, and other factors.

RX Antenna Gain

RX Antenna Gain (G_rx) represents the receiving antenna's gain in dBi.

The receiver antenna contributes to the received signal calculation. A higher-gain receiving antenna can improve the theoretical link budget, although antenna orientation, polarization, mounting, and installation environment remain important.

For directional antennas, orientation becomes especially important because the specified gain may only apply strongly in particular directions.

Total Cable and Connector Loss

RF energy can be lost before it reaches the antenna or receiver.

The calculator represents this through Total Cable/Connector Loss, entered in dB.

The implementation distributes the entered loss equally between the TX and RX sides. Therefore, the calculator uses half of the specified loss when calculating each side of the link.

The TX EIRP calculation is:

EIRP = P_tx + G_tx − L_cable/2

The received-power calculation uses another L_cable/2 term.

This means users should understand the calculator's loss model before entering their value. If you have separately measured TX-side and RX-side losses, make sure the total value is consistent with this implementation.

Spreading Factor

The calculator supports SF7 through SF12.

Spreading factor is one of the most important LoRa physical-layer parameters because it affects the signal's required SNR threshold and therefore the theoretical receiver sensitivity.

The calculator uses these SNR limits:

As SF increases, the calculator uses a more negative demodulator SNR requirement. This improves the calculated sensitivity.

However, higher SF is not simply "better." Higher spreading factors generally increase airtime, which can affect throughput, battery operation, and network capacity.

Bandwidth

The calculator accepts bandwidth in kHz and converts it internally to Hz for the sensitivity calculation.

The supported input range is approximately 7.8 to 500 kHz.

Bandwidth directly affects the thermal-noise component of the sensitivity equation:

Noise Floor = −174 + 10 × log₁₀(BW_Hz)

A wider bandwidth produces more integrated thermal noise, which raises the calculated noise floor. Therefore, bandwidth selection has a direct effect on theoretical receiver sensitivity.

Use the bandwidth corresponding to the actual LoRa configuration being evaluated.

Receiver Noise Figure

Receiver Noise Figure (NF) is entered in dB.

The calculator's default is 6 dB, with an input range from 1 to 20 dB.

Noise figure represents additional receiver noise relative to an ideal receiver. A lower noise figure generally allows better sensitivity under otherwise equivalent conditions.

When a radio or receiver datasheet provides a noise-figure specification appropriate to the operating configuration, that value is preferable to an arbitrary estimate.

Channel Path Loss

Channel Path Loss (PL) is the attenuation between the transmitter and receiver, expressed in dB.

The calculator accepts path-loss values from 0 to 200 dB.

Path loss can arise from propagation through free space as well as environmental effects such as:

• Buildings
• Walls
• Terrain
• Trees
• Vegetation
• Obstructions
• Diffraction
• Multipath conditions

The quality of the path-loss estimate has a major influence on the usefulness of the final link-margin result.

LoRa Receiver Sensitivity Calculation

Receiver sensitivity is one of the most important outputs of the calculator.

The implementation uses:

S_rx = −174 + 10 × log₁₀(BW_Hz) + NF + Required SNR

Each term has a specific role.

−174 dBm/Hz represents the commonly used thermal-noise density reference at room temperature.

BW_Hz determines how much bandwidth contributes to the integrated noise power.

NF accounts for additional receiver noise.

Required SNR comes from the calculator's SF-specific LoRa demodulator limits.

For example, increasing SF from SF7 to SF12 changes the required SNR from −7.5 dB to −20 dB in this calculator. That makes the theoretical sensitivity substantially more negative, assuming the other parameters remain unchanged.

The sensitivity calculation also shows why bandwidth matters. Increasing bandwidth increases the thermal-noise term, which makes calculated sensitivity less negative.

What Is LoRa Receiver Sensitivity?

LoRa receiver sensitivity is the minimum received signal level required for demodulation under specified conditions. In this calculator, sensitivity is estimated from bandwidth, receiver noise figure, and the selected SF's SNR limit.

A more negative sensitivity value indicates that the receiver can theoretically operate with a weaker received signal.

Understanding TX EIRP

EIRP, or Equivalent Isotropically Radiated Power, combines transmitter output power with antenna gain while accounting for the modeled TX-side cable loss.

The calculator uses:

EIRP = P_tx + G_tx − L_cable/2

Suppose the inputs are:

• TX power = 14 dBm
• TX antenna gain = 2.15 dBi
• Total cable/connector loss = 1 dB

Then:

EIRP = 14 + 2.15 − 0.5

EIRP = 15.65 dBm

EIRP provides a useful way to represent the effective radiated power after accounting for transmitter-side antenna gain and the modeled cable loss.

However, a calculated EIRP should not be treated as a statement of regulatory compliance. Permitted power and EIRP depend on the applicable frequency band, country, region, and radio rules.

Calculating Expected RX Power or RSSI

The calculator estimates received signal power using:

P_rx = EIRP − PL + G_rx − L_cable/2

Suppose:

• TX EIRP = 15.65 dBm
• Path loss = 135 dB
• RX antenna gain = 3 dBi
• Total cable loss = 1 dB

Then:

P_rx = 15.65 − 135 + 3 − 0.5

P_rx = −116.85 dBm

This is the expected received power based on the calculator's deterministic model.

It should not automatically be interpreted as the exact RSSI value that a physical LoRa transceiver will report. Real receivers operate in environments affected by noise, interference, fading, antenna mismatch, and other factors.

Maximum Allowable Path Loss (MAPL)

Maximum Allowable Path Loss (MAPL) represents the maximum path loss the calculated link can theoretically tolerate before the received signal reaches receiver sensitivity.

The calculator uses:

MAPL = EIRP + G_rx − L_cable/2 − S_rx

MAPL is particularly useful for preliminary network planning.

If your estimated path loss is significantly below MAPL, the link has theoretical room to tolerate additional attenuation.

If estimated path loss approaches MAPL, the link becomes increasingly sensitive to real-world variations.

If estimated path loss exceeds MAPL, the predicted received signal falls below the calculated sensitivity.

MAPL Is Not Maximum Distance

A common mistake is treating MAPL as a distance value.

MAPL is expressed in dB, not kilometers or miles.

To convert an allowable path loss into an estimated distance, you need a suitable propagation model that relates path loss to distance and environmental conditions. A free-space model may be useful in appropriate line-of-sight scenarios, but it cannot automatically represent every real-world LoRa deployment.

Understanding LoRa Link Margin

Link margin shows how far the predicted received signal sits above or below calculated receiver sensitivity.

The calculator uses:

Link Margin = P_rx − S_rx

For example, if:

• Expected RX power = −116.85 dBm
• Sensitivity = −136.03 dBm

then:

Link Margin = −116.85 − (−136.03)

Link Margin = 19.18 dB

The calculator classifies results using these thresholds:

These labels are the classification rules implemented by this particular calculator. They should not be interpreted as universal LoRa or LoRaWAN reliability standards.

A link with only a few decibels of theoretical margin has less room for unexpected attenuation than a link with a much larger margin.

Real-Life LoRa Link Budget Example: Rural Soil Monitoring

Consider a smart agriculture deployment where battery-powered soil sensors communicate with a LoRa gateway.

Suppose an engineering estimate uses:

• TX power: 14 dBm
• TX antenna gain: 2.15 dBi
• RX antenna gain: 3 dBi
• Total cable/connector loss: 1 dB
• SF: 12
• Bandwidth: 125 kHz
• Receiver noise figure: 6 dB
• Estimated path loss: 135 dB

Step 1: Calculate Receiver Sensitivity

The bandwidth is:

125 kHz = 125,000 Hz

The thermal noise calculation is:

−174 + 10 × log₁₀(125,000)

This gives approximately:

−122.03 dBm

For SF12, the calculator uses a required SNR of:

−20 dB

Adding the 6 dB receiver noise figure:

Sensitivity = −122.03 + 6 − 20

Sensitivity ≈ −136.03 dBm

Step 2: Calculate TX EIRP

The calculator distributes the 1 dB total cable loss equally:

Cable loss per side = 0.5 dB

Therefore:

EIRP = 14 + 2.15 − 0.5

EIRP = 15.65 dBm

Step 3: Calculate Expected RX Power

Now apply the path loss:

RX Power = 15.65 − 135 + 3 − 0.5

RX Power = −116.85 dBm

Step 4: Calculate Link Margin

Finally:

Link Margin = −116.85 − (−136.03)

Link Margin ≈ 19.18 dB

The calculator would classify this configuration as:

Excellent (High Reliability)

From the calculator's perspective, there is approximately 19.18 dB of theoretical margin.

However, this does not mean the sensor is guaranteed to work at that distance. The 135 dB path-loss assumption needs to represent the actual deployment environment. Antenna installation, terrain, vegetation, interference, and fading can all affect field performance.

This is exactly where a link-budget calculator becomes useful: it gives the engineer a quantitative starting point before physical deployment.

LoRa Link Budget Use Cases

Smart Agriculture

LoRa is widely suited to applications where small amounts of sensor data need to travel over relatively long wireless links.

Potential applications include:

• Soil moisture monitoring
• Temperature sensors
• Humidity monitoring
• Irrigation systems
• Weather stations
• Agricultural equipment monitoring

A link-budget calculation can help determine whether sensors positioned around a farm have sufficient theoretical margin to reach a gateway.

Smart City IoT

Urban deployments can use low-power wireless sensors for applications such as:

• Parking monitoring
• Environmental sensing
• Infrastructure monitoring
• Utility monitoring
• Waste-management systems

Buildings and other structures can significantly change the propagation environment, so an urban link should not be planned solely from straight-line distance.

Industrial Monitoring

Industrial facilities can present challenging RF environments because of machinery, metal structures, walls, and complex layouts.

Potential applications include:

• Tank-level monitoring
• Equipment telemetry
• Asset monitoring
• Machine-condition sensors
• Remote measurements

A link budget allows engineers to evaluate whether the available RF margin is sufficient before deploying additional gateways or changing antenna configurations.

Remote Environmental Monitoring

Remote sensing applications may place sensors far from gateways.

Examples include:

• Weather monitoring
• Water-level monitoring
• Forest sensing
• Remote infrastructure
• Environmental data collection

For these applications, antenna placement and path-loss assumptions can become particularly important.

LoRaWAN Gateway Planning

A link-budget calculation can support preliminary gateway planning by comparing different:

• Antenna gains
• Cable lengths
• SF configurations
• Receiver characteristics
• Path-loss assumptions

It is only one part of a complete LoRaWAN network design because capacity, airtime, interference, regulatory requirements, and gateway placement also matter.

How to Use the LoRa Link Budget Calculator

Using the calculator is straightforward.

1. Enter TX output power.
Use the transmitter's actual RF output power in dBm.

2. Enter TX antenna gain.
Use the antenna's specified gain in dBi.

3. Enter RX antenna gain.
Use the receiving antenna's gain.

4. Enter total cable and connector loss.
Follow the calculator's total-loss model.

5. Select the spreading factor.
Choose SF7 through SF12.

6. Enter bandwidth.
Use the actual LoRa bandwidth in kHz.

7. Enter receiver noise figure.
Use a known receiver specification where possible.

8. Enter estimated path loss.
Use a credible propagation estimate or measured value.

9. Review the calculated outputs.

The calculator returns:

• Calculated RX sensitivity
• TX EIRP
• Expected RX power
• Maximum Allowable Path Loss
• Link margin
• Demodulator SNR limit
• Link status

10. Validate the result.

If the result looks marginal, consider improving antenna placement, reducing cable loss, changing the RF configuration, or reassessing the propagation path.

LoRa Link Budget Formulas

For quick reference, the calculator uses the following equations.

Receiver Sensitivity

S_rx = −174 + 10 × log₁₀(BW_Hz) + NF + Required SNR

Where:

• S_rx = receiver sensitivity in dBm
• BW_Hz = bandwidth in Hz
• NF = receiver noise figure in dB
• Required SNR = SF-dependent demodulator threshold

TX EIRP

EIRP = P_tx + G_tx − L_cable/2

Expected RX Power

P_rx = EIRP − PL + G_rx − L_cable/2

Maximum Allowable Path Loss

MAPL = EIRP + G_rx − L_cable/2 − S_rx

Link Margin

Margin = P_rx − S_rx

These equations let you see exactly how changing an input affects the theoretical link.

How SF, Bandwidth, and Noise Figure Affect LoRa Performance

Three inputs have particularly important effects on calculated sensitivity.

Spreading Factor

Increasing SF makes the calculator's required SNR threshold more negative:

• SF7: −7.5 dB
• SF8: −10 dB
• SF9: −12.5 dB
• SF10: −15 dB
• SF11: −17.5 dB
• SF12: −20 dB

That improves calculated sensitivity and therefore increases theoretical link margin when everything else stays constant.

The tradeoff is increased airtime at higher spreading factors.

Bandwidth

Increasing bandwidth increases the integrated thermal-noise power.

As a result, the calculated receiver sensitivity becomes less favorable when all other parameters remain unchanged.

Bandwidth should therefore be selected based on the actual communication requirements rather than simply choosing the largest or smallest available value.

Noise Figure

A lower receiver noise figure reduces the receiver's noise contribution.

For the same bandwidth and SNR requirement, a lower NF produces a more favorable sensitivity calculation.

These three variables illustrate an important RF engineering principle: range, sensitivity, data rate, airtime, and network capacity are interconnected tradeoffs.

How to Improve a Weak LoRa Link

If the calculator shows a small or negative link margin, there are several potential engineering options.

Improve Antenna Gain

A better antenna can increase the theoretical link budget without necessarily increasing transmitter output power.

The antenna must still be appropriate for the operating frequency and properly installed.

Reduce Cable Loss

Long coaxial cable runs can introduce avoidable RF attenuation.

Reducing cable length or using an appropriate low-loss cable can preserve more RF power.

Improve Antenna Placement

Antenna height and obstruction clearance can have a major impact on propagation.

Moving an antenna away from nearby obstacles or improving its installation position can sometimes provide a larger practical improvement than simply increasing transmitter power.

Select an Appropriate SF

A higher spreading factor can improve the calculated sensitivity in this calculator, but it also introduces airtime and capacity tradeoffs.

Improve Receiver Performance

A receiver with a lower noise figure can provide better calculated sensitivity under equivalent conditions.

Reconsider Gateway Placement

Sometimes the most effective solution is changing the physical location of the gateway or sensor.

An improved propagation path can reduce path loss significantly.

Common LoRa Link-Budget Calculation Mistakes

Mistake 1: Confusing RSSI With Sensitivity

RSSI or received power describes the signal level arriving at the receiver. Sensitivity describes the minimum signal level needed for demodulation under defined conditions.

They are related, but they are not the same measurement.

Mistake 2: Assuming More TX Power Fixes Everything

Increasing transmit power may improve the budget, but it cannot eliminate problems caused by poor antenna placement, severe obstructions, interference, or regulatory restrictions.

Mistake 3: Ignoring Cable Loss

Cable and connector losses reduce the RF power available to the antenna or receiver.

Mistake 4: Treating Antenna Gain as Guaranteed Real-World Performance

Nominal antenna gain does not automatically account for installation conditions, orientation, polarization, nearby materials, or mismatch.

Mistake 5: Assuming Path Loss Equals Free-Space Loss

Real environments are more complicated than an ideal free-space model.

Mistake 6: Treating MAPL as Distance

MAPL is measured in dB. It represents allowable attenuation, not physical distance.

Mistake 7: Treating Calculator Status as a Guarantee

A calculated "Excellent" result does not guarantee a reliable physical deployment. The calculation depends on the accuracy of the inputs and does not explicitly model every real-world propagation effect.

LoRa Link Budget vs. LoRa Range Calculator

A LoRa link-budget calculator and a LoRa range calculator answer related but different questions.

A link-budget calculator is particularly useful when you already have an estimated path loss and want to know how much margin remains.

A range calculator is more appropriate when the primary question is how far a signal might travel under a selected propagation model.

For professional planning, both calculations can be useful, followed by field measurements.

Limitations of This LoRa Link Budget Calculator

This calculator is an engineering estimation tool. It does not explicitly model every factor that can influence a real LoRa link.

For example, the calculation does not directly model:

• Terrain profiles
• Fresnel-zone clearance
• Building penetration
• Multipath fading
• Shadowing
• Antenna mismatch
• VSWR
• Polarization mismatch
• Detailed frequency-specific propagation behavior
• Interference
• Receiver blocking
• LoRaWAN network capacity
• Duty-cycle restrictions
• Regional regulatory requirements

The calculated path loss is also user-provided. If the path-loss assumption is overly optimistic, the resulting link margin can be overly optimistic as well.

For this reason, the calculator should be used for preliminary RF planning and engineering analysis, followed by appropriate field validation.

Frequently Asked Questions

What is a LoRa link budget?

A LoRa link budget calculates the RF gains and losses between a transmitter and receiver and compares the predicted received power with receiver sensitivity. It helps determine whether a theoretical wireless link has enough margin to operate.

How do you calculate a LoRa link budget?

Calculate receiver sensitivity from bandwidth, noise figure, and the selected SF's SNR limit. Then calculate EIRP, subtract path loss, add receiver antenna gain, account for receiver-side losses, and compare the resulting received power with sensitivity.

What is LoRa receiver sensitivity?

Receiver sensitivity is the minimum received signal level required for demodulation under specified conditions. More negative sensitivity values represent weaker signals that can theoretically be received.

How does spreading factor affect LoRa sensitivity?

In this calculator, higher SF values use more negative demodulator SNR limits. SF7 uses −7.5 dB, while SF12 uses −20 dB. This produces better calculated sensitivity at higher SF when other inputs remain unchanged.

Does higher SF increase LoRa range?

Higher SF can improve theoretical link budget because of the improved sensitivity calculation. However, physical range also depends on path loss, antennas, obstructions, interference, and the propagation environment.

What is MAPL in LoRa?

MAPL stands for Maximum Allowable Path Loss. It represents the maximum attenuation that the calculated link can theoretically tolerate before the received signal reaches receiver sensitivity.

What is LoRa link margin?

Link margin is the difference between predicted received power and receiver sensitivity:

Margin = P_rx − S_rx

A larger positive value means more theoretical signal headroom.

What is a good LoRa link margin?

There is no single universal margin that guarantees reliability in every deployment. This calculator classifies 10 dB or more as "Excellent", but the appropriate engineering margin depends on the environment and required reliability.

Does higher bandwidth reduce LoRa range?

Under the sensitivity equation used by this calculator, increasing bandwidth increases integrated thermal noise and therefore makes calculated sensitivity less negative when the other parameters remain constant.

How do I calculate LoRa RSSI?

This calculator estimates received power using:

P_rx = EIRP − PL + G_rx − L_cable/2

The result is an expected RF received-power estimate, not necessarily the exact RSSI reading from a physical radio.

What path loss should I use for LoRa?

Use a path-loss value derived from an appropriate propagation model, measurement, or credible engineering estimate for the actual environment. Avoid assuming that free-space path loss accurately represents every deployment.

Can a LoRa link-budget calculator calculate exact range?

No. A link-budget calculator can estimate received power, sensitivity, allowable path loss, and link margin. Exact coverage depends on the propagation environment and normally requires a suitable propagation model and field testing.

Why can a real LoRa link fail even when the calculator shows positive margin?

Possible reasons include inaccurate path-loss estimates, fading, interference, poor antenna installation, polarization mismatch, cable losses, terrain, buildings, vegetation, and other environmental effects not represented by the simplified calculation.

Practical LoRa Link-Budget Checklist

Before deploying a LoRa link, verify the following:

• Confirm the operating frequency.
• Confirm the actual TX output power.
• Verify TX and RX antenna specifications.
• Account for cable and connector losses.
• Select the actual spreading factor.
• Select the actual bandwidth.
• Use a credible receiver noise figure.
• Estimate or measure path loss.
• Calculate receiver sensitivity.
• Calculate expected received power.
• Check MAPL.
• Check link margin.
• Consider an appropriate engineering margin.
• Validate the link with field measurements.
• Verify applicable regulatory requirements.

Key Takeaways

A LoRa Link Budget Calculator provides a structured way to evaluate the theoretical RF performance of a LoRa connection.

The most important concepts are:

• TX power determines the starting RF power.
• Antenna gain can increase the effective link budget.
• Cable and connector losses reduce available RF power.
• Path loss represents attenuation through the propagation path.
• Spreading factor affects the demodulator SNR requirement.
• Bandwidth affects the receiver's thermal-noise contribution.
• Noise figure affects calculated receiver sensitivity.
• MAPL indicates how much path loss the link can theoretically tolerate.
• Link margin shows how far predicted received power is above or below sensitivity.
• A positive margin does not guarantee real-world reliability.
• Field conditions, interference, antenna installation, and propagation effects must ultimately be considered.

For preliminary LoRa and LoRaWAN engineering, the calculator provides a practical way to move beyond simple "how far can LoRa reach?" questions and instead evaluate the actual RF power budget, receiver sensitivity, path loss, and available link margin.