RF Engineering Calculator Suite

Impedance · Conversions · Power · EMC & Field Strength · Circuits · Time-on-Air

Impedance Matching & Transformations

L-Network Matching

Calculate series/parallel reactive components for impedance matching.

Formulas:

Q = √(R_high / R_low − 1)
X_series = R_low × Q · X_parallel = R_high / Q

L = X/(2πf) · C = 1/(2πfX)

Frequency (MHz)

Source Zs (Ω) — Real / Imag

Load Zl (Ω) — Real / Imag

Result

Enter values and click Calculate

Impedance ↔ Component

Convert between reactance (Ω) and component values (pF, nH).

Formulas:

X_C = −1/(2πfC) → C = 1/(2πf|X|)
X_L = 2πfL → L = X/(2πf)

Frequency (MHz)

Impedance (Ω) — Real / Imag

Capacitance (pF)

Result

Enter values and click Calculate

Parallel & Series Impedance

Combine two complex impedances in series or parallel.

Formulas:

Z_series = Z1 + Z2
Z_parallel = (Z1 × Z2) / (Z1 + Z2)

Z1 (Ω) — Real / Imag

Z2 (Ω) — Real / Imag

Result

Enter values and click Calculate

Series → Parallel Equivalent

Convert series R+jX to parallel equivalent Rp || Xp, compute Y=1/Z.

Formulas:

R_p = |Z|²/Rs = Rs(1+Q²)
X_p = |Z|²/Xs
Q = |Xs|/Rs · Y = 1/Z

Frequency (MHz)

Series Z (Ω) — Rs / Xs

Result

Enter values and click Calculate

Unit Conversions

dBµV ↔ µV

Convert between voltage in dBµV and linear µV/mV/V.

Formulas:

dBµV = 20 × log₁₀(V_µV)
V_µV = 10^(dBµV/20)
dBmV = dBµV − 60 · dBV = dBµV − 120

dBµV

µV

Result

Enter values and click Calculate

dBm ↔ dBµV (50Ω)

Convert power (dBm) and voltage (dBµV) in a 50Ω system. Key offset: 107 dB.

Formulas:

P[dBm] = V[dBµV] − 107
V[dBµV] = P[dBm] + 107

0 dBm = 1mW → V=√(0.001×50) = 223.6mV = 107.0 dBµV

Power (dBm)

Voltage (dBµV)

Result

Enter values and click Calculate

Universal Field Unit Converter

Type in any field value — all others update live.

Relationships:

V/m ↔ µV/m: ×10⁶ / ÷10⁶
dBµV/m = 20×log₁₀(µV/m)
S[mW/m²] = E²[V/m] / 377 × 1000

E-Field (V/m)

E-Field (µV/m)

E-Field (dBµV/m)

Power Density S (mW/m²)

Impedance ↔ Admittance

Convert between Z (Ω) and Y (Siemens).

Formulas:

Y = 1/Z = (R − jX)/(R² + X²)
Z = 1/Y

Z (Ω) — Real / Imag

Y (S) — Real / Imag

Result

Enter values and click Calculate

Wavelength & Beta

Compute wavelength, quarter-wave, and propagation constant.

Formulas:

λ = c × VF / f
β = 2π / λ [rad/m]

c = 299 792 458 m/s

Frequency (MHz)

Velocity Factor (0–1)

Result

Enter values and click Calculate

Power Analysis & Efficiency

PAE — Power Added Efficiency

Drain efficiency and PAE from RF output and DC consumption.

Formulas:

η = P_out / P_DC × 100%
PAE = (P_out − P_in) / P_DC × 100%
P_DC = V × I · Gain = P_out − P_in [dB]

Output Power (dBm)

Supply Voltage (V)

Supply Current (mA)

Result

Enter values and click Calculate

dBm ↔ Watts

Convert between dBm and linear power.

Formulas:

P[mW] = 10^(P[dBm]/10)
P[dBm] = 10 × log₁₀(P[mW])

Power (dBm)

Power (mW)

Result

Enter values and click Calculate

EMC & Field Strength Conversions

E-Field → EIRP (source power)

From a measured E-field at distance d, compute the EIRP of the source. Looks backward toward the transmitter.

Linear:

EIRP[W] = E²[V/m] × 4π × d²[m] / η₀
E[dBµV/m] = 20 × log₁₀(E[µV/m])

Depends on distance d — does NOT depend on frequency. η₀ = 377 Ω

dB:

EIRP[dBm] = 20·log₁₀(E[µV/m] × d[m]) − 104.77

104.77 dB constant breakdown:
· µV/m → V/m: −120 dB
· 4π factor: +10.99 dB
· ÷ η₀ (377 Ω): −25.76 dB
· W → mW: +30 dB

E (µV/m)

E (V/m)

E (dBµV/m)

Distance d (m)

Result

Enter values and click Calculate

E-Field → Received Power (at DUT)

Power received by a DUT antenna in a known E-field. Looks forward toward the receiver. Used for ETSI immunity analysis.

Linear:

Pr[W] = E²[V/m] × G × λ²[m] / (4π × η₀) = S × Ae (S = E²/η₀ | Ae = Gλ²/4π)

dB (via Antenna Factor):

Pr[dBm] = E[dBµV/m] − AF[dB/m] − 107

AF [dB]: −29.8 + 20·log₁₀(f[MHz]) − G[dBi]
AF [linear]: 9.73/(λ√G)
−107 dB: dBµV/m→V/m (−120) + V→P/Z₀ (+13) + W→mW (+30)

E (dBµV/m)

E (V/m)

E (µV/m)

E (dBµV/m)

Frequency (MHz)

Antenna Gain (dBi)

Result

Enter values and click Calculate

FCC Part 15.209 Compliance

Check measured field against FCC limits. Normalizes to 3m and computes EIRP.

Method:

1. Normalize: E_3m = E_meas × (d/3)
2. Compare to band limit (µV/m @ 3m)
3. EIRP = E²_3m × 4π×9 / 377
Limits @ 3m: 30–88→100 · 88–216→150 · 216–960→200 · 960+→500 µV/m (−41.2 dBm)

Frequency (MHz)

Measured Field (µV/m)

Measured Field (dBµV/m)

Distance (m)

Result

Enter values and click Check

EIRP → E-Field at Distance

From a known EIRP, compute E-field at a given distance. Inverse of EIRP formula.

Formula:

E = √(EIRP × η₀ / (4π × d²))
E[µV/m] = E[V/m] × 10⁶

Inverse of EIRP = E²×4πd²/η₀

EIRP (dBm)

Distance (m)

Result

Enter values and click Calculate

Antenna Factor (AF)

Links E-field in air to voltage at antenna port (50Ω). Essential for EMC measurements.

Formulas:

AF = E / V [m⁻¹]
AF[dB/m] = −29.8 + 20×log₁₀(f[MHz]) − G[dBi]
Measurement: E[dBµV/m] = P[dBm] + 107 + AF + L_cable

+107 converts dBm → dBµV in 50Ω

Frequency (MHz)

Antenna Gain (dBi)

Result

Enter values and click Calculate

Free Space Path Loss (FSPL)

Signal attenuation between isotropic antennas in free space.

Formula:

FSPL = (4πd/λ)²
FSPL[dB] = 20×log₁₀(d[m]) + 20×log₁₀(f[MHz]) − 27.55

Or: 20×log₁₀(d[km]) + 20×log₁₀(f[MHz]) + 32.45

Frequency (MHz)

Distance (m)

Result

Enter values and click Calculate

Circuit Analysis

LC Resonance

Compute resonant frequency, or find L/C for a target.

Formulas:

f₀ = 1 / (2π√(LC))
Z₀ = √(L/C)

L = 1/(4π²f²C) · C = 1/(4π²f²L)

Frequency (MHz)

Inductance (nH)

Capacitance (pF)

Result

Enter values and click Calculate

Delta ↔ Y Transformation

Convert between delta (Δ) and star (Y) networks.

Formulas:

Δ→Y: Z1 = Zb×Zc/(Za+Zb+Zc)
Y→Δ: Za = (Z1Z2+Z2Z3+Z3Z1)/Z1

Za (Ω)

Zb (Ω)

Zc (Ω)

Result

Enter values and click Calculate

Time-on-Air Calculator

Modulation Parameters

LoRa PHY layer settings.

Region / Standard

Duty cycle: ~1% (EU868)

Spreading Factor

Bandwidth

Coding Rate

Preamble Symbols

Header Mode

CRC Enabled

PHY Payload (bytes)

LDRO

Auto: OFF (T_sym < 16 ms at current SF/BW)

LoRaWAN Payload Builder

Computes PHY frame size from application data length. Ref: LoRaWAN spec v1.0.3 §4 / Table 112

Frame Type — sets PHY parameters per LoRaWAN spec Table 112

PHY = MHDR(1) + DevAddr(4) + FCtrl(1) + FCnt(2) + FOpts(0-15) + FPort(1) + AppPayload + MIC(4)

Minimum overhead (no FOpts): 13 bytes

App Payload (bytes)

FPort (0–223)

FOpts length (bytes, 0–15)

PHY frame
25 B

MAC payload
20 B

Overhead
13 B

Battery Life Estimate

Rough estimate based on TX duty and idle current.

TX Interval (min)

TX Current (mA)

Idle Current (µA)

Battery (mAh)

Adjust parameters above

Configure parameters on the left to compute Time-on-Air

Spreading Factor Comparison

All SFs at current BW / CR / payload — highlighted row is active selection.

Formula Reference

① Symbol duration

T_sym [s] = 2^SF / BW [Hz]

② Preamble time

T_pre [s] = (n_preamble + 4.25) × T_sym

4.25 = 2 Sync Word symbols + 2.25 SFD symbols (fixed LoRa preamble tail)

③ Payload symbol count

num = 8·PL − 4·SF + 28 + 16·CRC − 20·IH
den = 4·(SF − 2·DE)
n_pay = 8 + max(⌈num / den⌉, 0) × (CR + 4)

Numerator terms
8·PL — raw payload data bits
+28 — fixed LoRa overhead: 8 tail bits + 6 header bits × CR encoding (explicit mode baseline)
+16·CRC — adds 16 bits when PHY CRC is enabled
−4·SF — subtracts the data bits already carried by the initial 8 header symbols
−20·IH — removes 20 bits of header when implicit header mode is used
Denominator
4·(SF−2·DE) — data bits per coding block; DE=1 reduces effective SF by 2 (forces 2-byte interleaving to avoid inter-symbol interference at slow data rates)
Result
8 — the first 8 symbols are always present (header region for explicit mode)
⌈num/den⌉ — ceiling division: number of coding blocks needed to carry the remaining bits
(CR+4) — symbols per coding block (CR=1→4/5: 5 sym · CR=4→4/8: 8 sym)
max(…, 0) — clamp to zero for very short payloads at high SF

④ Total packet time

T_pkt [s] = T_pre + n_pay × T_sym

Parameter definitions

SF	Spreading Factor (5 – 12)
BW	Bandwidth in Hz (e.g. 125 000 for 125 kHz)
n_preamble	Preamble length in symbols (default 8)
PL	Payload length in bytes
CRC	1 if CRC enabled, 0 if disabled
IH	1 if implicit header, 0 if explicit header
CR	Coding rate index: 1 = 4/5 · 2 = 4/6 · 3 = 4/7 · 4 = 4/8
DE	Low Data-Rate Optimize: 1 if ON, 0 if OFF (auto: ON when T_sym ≥ 16 ms)

Ref: SX1261/2 DS §6.1 · LR1121 UM §8.2 · AN1200.13

Modem Parameters

GFSK / FSK radio settings

Bit Rate

ℹ RF parameters not shown — Gaussian filter (BT), modulation index (h), frequency deviation (Fdev) and data whitening (XOR scrambling) affect spectral occupancy and receiver sensitivity only. They have no impact on frame duration or Time-on-Air.

Packet Structure

LR2021 / LR11xx / SX126x variable / fixed-length GFSK frame fields

Preamble (bytes)

Sync Word length

Header / Length field

Payload (bytes)

CRC

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute GFSK Time-on-Air

Bit-Rate Comparison

All standard rates with current packet config — highlighted row is active selection.

Formula Reference

Time-on-Air

ToA [s] = N_total_bits / BitRate [bps]

Total frame length

N_total_bits =
preamble_length [bits]
+ sync_word_length [bits]
+ header_length [bits] ← variable-length mode only
+ payload_length [bits]
+ crc_length [bits]

Field sizes

Preamble	user-defined (bits) — typical 32–64 bits
Sync Word	0 – 64 bits (0 – 8 bytes, all chips)
Header	0 bits (fixed) · 8 bits (var, all) · 9 bits (SX128x compat) · 16 bits (LR2021)
Payload	user-defined (bytes × 8) — max 255 B (SX126x/LR11xx) · 65535 B (LR2021)
CRC	0 / 8 / 16 bits (SX126x/LR11xx) · 0 – 32 bits (LR2021)

Ref: SX1261/2 DS §6.2 · LR1121 UM §8.4 · LR2021 DS §11

Modem Parameters

FLRC per LR2021 V1.1 §18

Bit rate / channel BW

FEC coding rate

Packet Structure

§18.2 / §18.3 — Fig 18-1 (fixed) / Fig 18-2 (variable).

AGC Preamble

Sync word length

Packet format

Payload (bytes)

CRC (§18.2)

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute FLRC Time-on-Air

Bit-Rate Comparison

Standard FLRC profiles with current packet and FEC settings

Formula Reference

Time-on-Air — LR2021 §18.3

ToA_FLRC = t_bit × (n_uncoded + n_coded)
t_bit = 1 / R_b
n_uncoded = n_AGCPreamble + 21 + n_SyncWord + n_header
n_Preamble = 21 bits — fixed timing-recovery preamble (§18.2, not configurable)
n_header = 16 bits (variable format) | 0 (fixed)
n_coded = ceil[ (n_Payload + n_CRC + n_tail) × (1 / n_CR) ]
n_tail = 6 bits if CR = 1/2 or CR = 3/4 | 0 otherwise

n_CR: coded rate — 1 (off), 3/4, 2/3, or 1/2 (Table 18-2). n_tail = 0 for CR = 2/3 (only non-zero for CR 1/2 and 3/4).

Packet structure (§18.2)

Bit rate / BW pairs — Table 18-1

260 kbps … 2.6 Mbps. AGC preamble min: 16 b (2 B) for BR ≥ 650 kbps · 8 b (1 B) for BR < 650 kbps.

Ref: Semtech LR2021 V1.1 datasheet §18 — FLRC modem.

Modem Parameters

OOK per LR2021 V1.1 §20 & §11 (shared GFSK packet handler)

Chip Rate — BitRate

Encoding — Manchester

Packet Structure

LR2021 OOK

Preamble (bytes)

Sync Word length

Packet format

Address comparison

Payload (bytes)

CRC

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute OOK Time-on-Air

Bit-Rate Comparison

Standard LR2021 OOK rates with current packet config — includes RF-on time estimate.

Formula Reference

Time-on-Air — LR2021 §20 (OOK Modem)

ToA = N_chips / R_chip
NRZ: N_chips = N_pre×8 + N_sync×8 + N_hdr + N_pay×8 + N_crc×8
Manchester: N_chips = 2 × NRZ_value (every field ×2)

Manchester (SetOokPacketParams DataInversion): each data bit expands to 2 on-air chips → data rate = chip rate ÷ 2. RF-on is always exactly 50 % for all fields.

pkt_format — header size (SetOokPacketParams)

0x00 → N_hdr = 0 b (fixed length, no header transmitted)
0x01 → N_hdr = 8 b (variable, 8-bit payload length)
0x02 → N_hdr = 9 b (variable, 9-bit / SX128x compat)
0x03 → N_hdr = 16 b (variable, 16-bit: 15 LSBs = length, MSB = RFU)

CRC covers payload only (fixed) or header + payload (variable).

CRC — Crc (SetOokPacketParams / Table 11-7)

0x00 = off · 0x01 = 1 B · 0x02 = 2 B · 0x03 = 3 B · 0x04 = 4 B
0x09 = 1 B inv · 0x0A = 2 B inv · 0x0B = 3 B inv · 0x0C = 4 B inv

CRC bytes are appended at the end of the frame. Inverted variants apply bitwise NOT to the CRC output.

BitRate register encoding — SetModulationParams

BitRate(31) = 0 → bps = BitRate(30:0) (integer bps, direct)
BitRate(31) = 1 → bps = BitRate(30:0) / 256 (fractional precision)

LR2021 OOK Tx (Table 3-8, BROOK): 1.2 – 32.768 kbps. Standard integers: 1.2 · 2.4 · 4.8 · 6.4 · 9.6 · 12.5 · 25 kbps → mode 0. 50 kbps supported by SX128x only. Non-integer rates: use mode 1 (BitRate(30:0)/256).

Modem Parameters

Wireless M-Bus — EN 13757-4 · LR1121

WM-Bus mode

Preamble (bytes)

Packet Structure

EN 13757-4 Frame Type A — fixed overhead: L+C+M+A+CI = 11 B

Application data (bytes)

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute WM-Bus Time-on-Air

Mode Comparison

All EN 13757-4 modes at current application data payload.

Formula Reference

SetWmbusParams — Mode codes (LR2021 DS §12.3.1)

0x0=S · 0x1=T1 · 0x2=T2mRx · 0x3=T2mTx · 0x4=R2
0x5=C1 · 0x6=C2mRx · 0x7=C2mTx
0x8=N4.8k · 0x9=N2.4k · 0xA=N6.4k · 0xB=N19.2k · 0xC=F2

pbl_len_tx = preamble in bits. pld_len = C+M+A+CI+data bytes (excludes CRCs). rx_bw = 0xFF → auto-set by firmware.

Frame Type A structure (EN 13757-4 §7 / LR2021 STD_WM-BUS A)

[Preamble] [Sync] | L(1B) | C(1)+M(2)+A(6)+CRC₁₆(2) | CI(1)+Data+CRC₁₆(2)×…

L (= pld_len) = C+M+A+CI+data, excludes L itself and CRCs. Max L = 255 → max app data = 245 B. CRC polynomial: 0x3D65 (CRC-16/EN13757).

CRC block structure (Frame Type A)

Block 1: C(1)+M(2)+A(6) = 9 B → CRC-16 (2 B)
Block 2+: CI(1)+data in 16 B chunks → CRC-16 (2 B) per chunk
Total CRC OH = 2 + ⌈(1+N_app)/16⌉ × 2 B

Time-on-Air formula

ToA = N_chips / R_chip
NRZ: N_chips = Pre×8 + Sync×8 + N_frame×8
Manchester: N_chips = Pre×8 + Sync×8 + N_frame×16
3-out-of-6: N_chips = Pre×8 + Sync×8 + N_frame×12

Pre and Sync are always sent as raw chips (never Manchester/3-of-6 encoded). Frame data (from L field onwards) is encoded.

Encoding per mode (LR2021 Table 12-1)

Manchester (S, T2mRx, R2): each bit→2 chips · 16 chips/byte
3-out-of-6 (T1, T2mTx): each nibble→6 chips · 12 chips/byte
NRZ (C1/2, N*, F2): each bit→1 chip · 8 chips/byte

Modem Parameters

Z-Wave — ITU-T G.9959 · LR2021 §14

Z-Wave mode

Preamble (bytes)

Packet Structure

Z-Wave MPDU — fixed overhead: R1/R2/R3 = 9 B · LR1 = 12 B (excl. FCS)

Application payload (bytes)

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute Z-Wave Time-on-Air.

Mode Comparison

All Z-Wave modes at current payload — each mode uses its own default preamble length.

Formula Reference

SetZwaveParams — Mode values (LR2021 DS §14.3.1)

0x0=LR1 · 0x1=R1 · 0x2=R2 · 0x3=R3

pbl_len_tx = preamble in bits (set 0 for auto-minimum). pld_len = MPDU excluding FCS (FcsMode=0). rx_bw=0xFF → auto.

Modulation (LR2021 Table 14-1)

R1: 2FSK · Manchester · 19.2 ksps chip · mod index 2.08 · eff 9.6 kbps
R2: 2FSK · NRZ · 40 ksps = 40 kbps · mod index 1.0
R3: 2GFSK · NRZ · BT=0.6 · 100 ksps = 100 kbps · mod index 0.58
LR1: O-QPSK · 25 ksps · 2 bits/sym · mod index 0.5 · eff 50 kbps

Frame structure — R1/R2/R3 (Classic Z-Wave, ITU-T G.9959)

[Preamble] [SOF 1B] [HomeID 4B] [SrcNodeID 1B]
[FrameCtrl 2B] [Length 1B] [DstNodeID 1B] [Payload] [FCS 1B]
pld_len = HomeID+Src+FrameCtrl+Len+Dst+Payload = 9+N_pay

FCS = CRC-8 / XOR checksum · 1 B · auto-generated (FcsMode=0). HomeID filtering via addr_comp parameter.

Frame structure — LR1 (Z-Wave Long Range)

[Preamble] [SOF 2B] [HomeID 4B] [SrcNodeID 2B] [RSSI 1B]
[FrameCtrl 2B] [Length 1B] [DstNodeID 2B] [Payload] [FCS 2B]
pld_len = HomeID+Src+RSSI+FrameCtrl+Len+Dst+Payload = 12+N_pay

FCS = CRC-16 · 2 B · auto-generated in Tx. ⚠ WARNING: in LR1 Rx, the developer must wait for RxDone IRQ and calculate CRC-16 manually (LR2021 §14.2). NodeIDs are 12-bit (2 B field).

Time-on-Air formula

ToA = N_{total_bytes} × 8 / R_eff
R1 eff = 9 600 bps (chip 19 200 / Manchester factor 2)
R2 eff = 40 000 bps (NRZ direct)
R3 eff = 100 000 bps (NRZ GFSK direct)
LR1 eff = 50 000 bps (25 000 sym/s × 2 bits/sym O-QPSK)

All frame bytes (preamble, SOF, header, payload, FCS) share the same effective bit rate. R1 Manchester encoding doubles on-air chips (2 chips/bit at 19.2 ksps).

Modem Parameters

Wi-SUN FSK — IEEE 802.15.4g · LR2021 §13

Wi-SUN mode

Preamble (bytes)

FEC (fec_tx)

Packet Structure

IEEE 802.15.4g SUN-FSK — fixed overhead: SFD(2)+PHR(2)+MHR(9–21)+FCS(2–4)

Addressing (MHR)

FCS type (fcs_tx)

Application payload (bytes)

Duty Cycle & Interval

DC limit (%)

TX period (s)

Configure parameters on the left to compute Wi-SUN FSK Time-on-Air.

Mode Comparison

All Wi-SUN modes at current payload — no FEC, default preamble (8 B), short addressing.

Formula Reference

SetWisunMode — Mode values (LR2021 §13.3.1)

0x0=1a · 0x1=1b · 0x2=2a · 0x3=2b · 0x4=3 · 0x5=4a · 0x6=4b · 0x7=5

rx_bw=0xFF → auto. Profiles: ECHONET, FAN, RLMM, JUTA.

Modulation — all 2FSK NRZ (LR2021 Table 13-1)

1a/1b: 50 ksps · mod 0.5 / 1.0 · eff 50 kbps
2a/2b: 100 ksps · mod 0.5 / 1.0 · eff 100 kbps
3: 150 ksps · mod 0.5 · eff 150 kbps
4a/4b: 200 ksps · mod 0.5 / 1.0 · eff 200 kbps
5: 300 ksps · mod 0.5 · eff 300 kbps

2FSK NRZ: 1 bit per symbol → effectiveBps = symbolRate. Tolerance: ±100 ppm on all modes.

Frame structure (IEEE 802.15.4g SUN-FSK)

[Preamble] [SFD 2B] [PHR 2B] [MHR] [Payload] [FCS 2|4B]
↑ not FEC-encoded ↑ ↑————— PSDU — FEC-encoded when enabled ————↑
frame_len_tx = MHR + Payload (FCS excluded, crc_on=1)

SFD = 2 B (0x2A7E / 0x7A0E). PHR = 2 B (frame length + FCS type + whitening). frame_len_tx set via SetWisunPacketParams or SetWisunPacketLen.

MHR addressing (IEEE 802.15.4g)

Short (2B addr): FCF(2)+SN(1)+PAN(2)+Dst(2)+Src(2) = 9 B
Extended (8B addr): FCF(2)+SN(1)+PAN(2)+Dst(8)+Src(8) = 21 B

FEC (fec_tx — SetWisunPacketParams)

0x0 = None
0x1 = NRNSC rate½ + interleaver
0x2 = RSC rate½ (no interleaver)
0x3 = RSC rate½ + interleaver

FEC applies to PSDU only. Rate ½ → PSDU coded bits = 2 × raw bits → ToA of PSDU portion doubled. Preamble, SFD, PHR remain unencoded.

Time-on-Air formula

T_pre = N_pre × 8 / R_sym
T_SFD+PHR = 4 × 8 / R_sym (not FEC)
T_PSDU = N_PSDU × 8 × k_FEC / R_sym
ToA = T_pre + T_SFD+PHR + T_PSDU
k_FEC = 1 (no FEC) or 2 (rate-½ FEC)

IQ viewer Spectral and temporal

🖱 Scroll = zoom 🖱 Drag = pan 🖱 Dbl-click = reset view ⟷ Time plots (rows 2–5) share linked zoom

Ready — load a CSV file (I,Q per line) or click Demo. CSV format: one sample per line · two columns (I, Q) · delimiter: comma / space / tab