Decentralized Sequential Hypothesis Testing using Asynchronous Communication

TL;DR

This paper introduces an asymptotically optimal decentralized sequential hypothesis test that operates with asynchronous, limited 1-bit communication between sensors and a fusion center, applicable in both continuous and discrete time settings.

Contribution

It proposes a new SPRT-like test for decentralized hypothesis testing that achieves strong asymptotic optimality with minimal communication overhead.

Findings

Test is order-2 asymptotically optimal in continuous time.

Order-1 optimality under certain conditions in discrete time.

Simulations confirm excellent performance.

Abstract

We present a test for the problem of decentralized sequential hypothesis testing, which is asymptotically optimum. By selecting a suitable sampling mechanism at each sensor, communication between sensors and fusion center is asynchronous and limited to 1-bit data. The proposed SPRT-like test turns out to be order-2 asymptotically optimum in the case of continuous time and continuous path signals, while in discrete time this strong asymptotic optimality property is preserved under proper conditions. If these conditions do not hold, then we can show optimality of order-1. Simulations corroborate the excellent performance characteristics of the test of interest.