Experiment

Link configuration

01 Payload

Message51 chars

SeedDurationseconds

Interleaver

02 Watterson channel

PresetSNR in 3 kHz18.0 dB

Path editor 2 paths

PathDelay msPower dBShift Hz2σ Hz

03 Receiver

Carrier offsetHzInitial phasedeg

21-tap NLMS equalizer

Timing & equalizer advanced

TimingsymbolsClock errorppmEQ tapsNLMS μ

04 Carrier recovery

Probe-aided WLSWeighted phase/frequency fit across known probe blocks.Blind 8th-powerFeed-forward acquisition with ambiguity resolved by preamble.Decision-directed PLLPreamble acquisition followed by a second-order loop.No recoveryDiagnostic reference with carrier correction bypassed.REFOracleUses the known impairment as an upper-bound reference.REF

Probe-aided WLS parameters tune

Interpolation smoothing

Decoder lockLOCKED preamble + probes

Coded-bit BER1.90e-4 before Viterbi decode

Payload BER0 after Viterbi decode

RMS EVM8.7 %recovered symbols

Residual CFO+0.08 Hzinput +23 Hz

Equalizer MSE4.10e-3 21 taps · NLMS

TX audio · 1,800 Hz

Transmit waveform

48 kHz

RX distorted audio

Channel output

18.0 dB

TX / RX overlay

Occupied spectrum

300–3,300 Hz

TXRX

Mapper output

Ideal

8-PSK

Matched filter output

Before recovery

unlocked

Probe-aided WLS

Recovered

locked

True / estimated · 0.08 Hz residual

Carrier estimate

TrueEstimateResidual

Complex path magnitude

Watterson tap history

P1P2

Payload

Decoder comparison

exact match

TRANSMITTED

HF link check — MIL-STD-188-110B recovery trial 07.

RECOVERED · PROBE-AIDED WLS

HF link check — MIL-STD-188-110B recovery trial 07.