Systems and methods for low data rate, low power bi-directional transmissions over existing physical communication media

Abstract

Low data rate, low power, bi-directional transmissions may be provided over existing physical communication media (e.g., coaxial cables and/or optical fiber) and in the presence of higher bandwidth, higher power primary signals currently being transmitted over the communication media. The low data rate, low power, bi-directional transmissions may be accomplished using spread-spectrum modulated signals that are positioned in frequency relative to the primary signals, such that the low data rate, low power transmissions occur without detectable interference with the primary signals, which include multiplexed narrowband modulated signals. In some embodiments, the primary signals may be modulated using quadrature amplitude modulation (QAM) and multiplexed using orthogonal frequency division multiplexing (OFDM) and the spread-spectrum modulated signals may be chirp spread spectrum (CSS) modulated signals modulated using Gaussian frequency shift keying (GFSK). One example of the spread-spectrum modulated signals is implemented using LoRa technology and communication protocols defined by the LoRaWAN standard.