Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers

Determining the loop noise bandwidth and the coherent integration time is essential and important for the design of a reliable digital phase-locked loop (DPLL) in global navigation satellite system (GNSS) receivers. In general, designers set such parameters approximately by utilizing the well-known...

Full description

Bibliographic Details
Main Authors: Young-Jin Song, Thomas Pany, Jong-Hoon Won
Format: Article
Language:English
Published: MDPI AG 2023-06-01
Series:Sensors
Subjects:
Online Access:https://www.mdpi.com/1424-8220/23/13/5887
_version_ 1827734469130321920
author Young-Jin Song
Thomas Pany
Jong-Hoon Won
author_facet Young-Jin Song
Thomas Pany
Jong-Hoon Won
author_sort Young-Jin Song
collection DOAJ
description Determining the loop noise bandwidth and the coherent integration time is essential and important for the design of a reliable digital phase-locked loop (DPLL) in global navigation satellite system (GNSS) receivers. In general, designers set such parameters approximately by utilizing the well-known fact that the DPLL is stable if the normalized bandwidth, which is the product of the integration time and the noise bandwidth, is much less than one. However, actual limit points are not fixed at exactly one, and they vary with the loop filter order and implementation method. Furthermore, a lower limit on the normalized bandwidth may exist. This paper presents theoretical upper and lower limits for the normalized bandwidth of DPLL in GNSS receivers. The upper limit was obtained by examining the stability of DPLL with a special emphasis on the digital integration methods. The stability was investigated in terms of <i>z</i>-plane root loci with and without the consideration of the computational delay, which is a delay induced by the calculation of the discriminator and the loop filter. The lower limit was analyzed using the DPLL measurement error composed of the thermal noise, oscillator phase noise, and dynamic stress error. By utilizing the carrier-to-noise density ratio threshold which indicates the crossing point between the measurement error and the corresponding threshold, the lower limit of the normalized bandwidth is obtained.
first_indexed 2024-03-11T01:29:31Z
format Article
id doaj.art-91cb1b90c028481591384f5f647a7b4e
institution Directory Open Access Journal
issn 1424-8220
language English
last_indexed 2024-03-11T01:29:31Z
publishDate 2023-06-01
publisher MDPI AG
record_format Article
series Sensors
spelling doaj.art-91cb1b90c028481591384f5f647a7b4e2023-11-18T17:28:15ZengMDPI AGSensors1424-82202023-06-012313588710.3390/s23135887Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS ReceiversYoung-Jin Song0Thomas Pany1Jong-Hoon Won2Autonomous Navigation Laboratory, Department of Electrical and Computer Engineering, Inha University, Incheon 22212, Republic of KoreaInstitute of Space Technology and Space Applications, University of Federal Armed Forces Munich, 85577 Neubiberg, GermanyDepartment of Electrical Engineering, Inha University, Incheon 22212, Republic of KoreaDetermining the loop noise bandwidth and the coherent integration time is essential and important for the design of a reliable digital phase-locked loop (DPLL) in global navigation satellite system (GNSS) receivers. In general, designers set such parameters approximately by utilizing the well-known fact that the DPLL is stable if the normalized bandwidth, which is the product of the integration time and the noise bandwidth, is much less than one. However, actual limit points are not fixed at exactly one, and they vary with the loop filter order and implementation method. Furthermore, a lower limit on the normalized bandwidth may exist. This paper presents theoretical upper and lower limits for the normalized bandwidth of DPLL in GNSS receivers. The upper limit was obtained by examining the stability of DPLL with a special emphasis on the digital integration methods. The stability was investigated in terms of <i>z</i>-plane root loci with and without the consideration of the computational delay, which is a delay induced by the calculation of the discriminator and the loop filter. The lower limit was analyzed using the DPLL measurement error composed of the thermal noise, oscillator phase noise, and dynamic stress error. By utilizing the carrier-to-noise density ratio threshold which indicates the crossing point between the measurement error and the corresponding threshold, the lower limit of the normalized bandwidth is obtained.https://www.mdpi.com/1424-8220/23/13/5887coherent integration timeglobal navigation satellite system (GNSS) receiverloop noise bandwidthnormalized bandwidthphase-locked loop (PLL)signal tracking loop
spellingShingle Young-Jin Song
Thomas Pany
Jong-Hoon Won
Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
Sensors
coherent integration time
global navigation satellite system (GNSS) receiver
loop noise bandwidth
normalized bandwidth
phase-locked loop (PLL)
signal tracking loop
title Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
title_full Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
title_fullStr Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
title_full_unstemmed Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
title_short Theoretical Upper and Lower Limits for Normalized Bandwidth of Digital Phase-Locked Loop in GNSS Receivers
title_sort theoretical upper and lower limits for normalized bandwidth of digital phase locked loop in gnss receivers
topic coherent integration time
global navigation satellite system (GNSS) receiver
loop noise bandwidth
normalized bandwidth
phase-locked loop (PLL)
signal tracking loop
url https://www.mdpi.com/1424-8220/23/13/5887
work_keys_str_mv AT youngjinsong theoreticalupperandlowerlimitsfornormalizedbandwidthofdigitalphaselockedloopingnssreceivers
AT thomaspany theoreticalupperandlowerlimitsfornormalizedbandwidthofdigitalphaselockedloopingnssreceivers
AT jonghoonwon theoreticalupperandlowerlimitsfornormalizedbandwidthofdigitalphaselockedloopingnssreceivers