Some embodiments include an apparatus, method, and computer program product for secure time-of-arrivals calculations in an ultra-wideband (UWB) system. Some embodiments include a UWB receiver that can inspect a channel impulse response (CIR) between a first and second electronic device and identify one or more first path candidates (FPCs). For a candidate path, the UWB receiver can identify subsequent paths that create inter-pulse interference (IPI) on the candidate path. Using estimates for the interfering path strengths (e.g., channel coefficients from the CIR) and the known cryptographically sequence of pulse polarities (SPP), the UWB receiver can reduce the IPI from these interfering paths on the FPCs, and then make decisions based at least on the remaining pulse polarities, whether the one or more FPCs comprise a legitimate transmission signal.