Pulse Position Coded Medium Access in energy-starved networks

Abstract

This paper presents a novel pulse position-coded PDU (PPCP) paradigm for multi-access wireless sensor nodes and IoT networks with thin energy budgets. The core idea is to encode a protocol data unit (PDU) in terms of the silence duration between two sets of delimiter pulses, whose positions are modulated based on the value of the PDU. This PPCP architecture achieves significant energy savings by using a lesser amount of bit/pulse transmissions, and by eliminating long multi-bit preambles and headers, which are normally used in traditional packets. The proposed multi-access pulse-based PDU scheme enables medium sharing among many sensor nodes without requiring per-PDU frame synchronization. Unlike previous Communication through Silence (CtS) literature, a full architecture design and prototype hardware platform of PPCP is presented here to demonstrate its advantages in terms of energy savings, reduced transmission delays, and ease of implementation. The advantages of PPCP compared to state-of-the-art Bluetooth Low Energy (BLE) and legacy binary packets are also shown. The prototype implementation shows reliable error detection based on a novel mechanism that relies on the inherent pulse-position modulation-based coding technique.