Type-Based Multiple Access for massive connectivity: design and implementation aspects
Author
Massanet Ginard, Michel
Term
4. term
Education
Publication year
2020
Submitted on
2020-06-04
Pages
64
Abstract
This thesis investigates Type-Based Multiple Access (TBMA) as a scalable communication and inference method for massive Internet of Things (IoT) deployments that monitor a Quantity of Interest (QoI). In TBMA, devices map their local measurements to types so the receiver can infer the QoI from the histogram of received types rather than individual payloads. We develop a system and signal model, define a TBMA communication protocol, and propose three transmission schemes with different requirements for channel and timing compensation (TS1: channel and timing advance compensation; TS2: phase and timing advance compensation; TS3: uncontrolled transmission). Narrowband IoT (NB-IoT) is adopted as the baseline technology due to its narrow bandwidth and low-power operation, and the protocol is adapted to the NB-IoT physical layer with emphasis on NPRACH preambles. Performance is evaluated in terms of estimation error probability for two representative scenarios: a binary-state QoI and a multi-state QoI. The results quantify how the number of available preambles and the number of QoI states constrain TBMA performance, pointing to minimum preamble requirements and an upper bound on QoI granularity under given conditions. We further examine implementation aspects when integrating TBMA into a practical NB-IoT system and discuss alternatives to mitigate system limitations.
Dette speciale undersøger Type-Based Multiple Access (TBMA) som en skalerbar kommunikations- og inferensmetode til massiv Internet of Things (IoT)-tilslutning, hvor mange enheder overvåger en størrelsesparameter (Quantity of Interest, QoI). I TBMA mapper enheder deres lokale målinger til typer, så modtageren kan udlede QoI ud fra histogrammet af modtagne typer i stedet for individuelle nyttedata. Vi udvikler et system- og signalmodel, definerer en TBMA-kommunikationsprotokol og foreslår tre transmissionsskemaer med forskellige krav til kanal- og timingkompensation (TS1: kanal- og timing advance-kompensation; TS2: fase- og timing advance-kompensation; TS3: ukontrolleret transmission). Narrowband IoT (NB-IoT) vælges som basisteknologi på grund af sin smalle båndbredde og lave strømforbrug, og protokollen tilpasses NB-IoT’s fysiske lag med fokus på NPRACH-præambler. Ydelsen vurderes ved estimeringsfejlsandsynlighed for to repræsentative scenarier: en binær QoI og en multi-tilstands QoI. Resultaterne kvantificerer, hvordan antallet af tilgængelige præambler og antallet af QoI-tilstande begrænser TBMA’s ydeevne, og peger på minimumskrav til præambler samt en øvre grænse for QoI-opdeling under givne forhold. Derudover behandles implementeringsaspekter ved integration af TBMA i et praktisk NB-IoT-system, og mulige alternativer for at imødegå systembegrænsninger diskuteres.
[This apstract has been generated with the help of AI directly from the project full text]