MIMO radar networks with incoherent sensor nodes

Erstveröffentlichung
2021-01-19Authors
Frischen, Andreas
Referee
Waldschmidt, ChristianStelzer, Andreas
Dissertation
Faculties
Fakultät für Ingenieurwissenschaften, Informatik und PsychologieInstitutions
Institut für MikrowellentechnikSeries
Schriftenreihe des Instituts für Mikrowellentechnik ; 8
Waldschmidt, Christian (Hrsg.)
Universität Ulm / Institut für Mikrowellentechnik (Hrsg.)
Waldschmidt, Christian (Hrsg.)
Universität Ulm / Institut für Mikrowellentechnik (Hrsg.)
Abstract
Multiple-Input Multiple-Output (MIMO) radars constitute a proven approach
to realize cost-efficient high-precision environment sensing solutions. Its vari-
ant with widely distributed antennas benefits from spatial diversity, offering
a large field of view and avoiding ghost targets. Until recently, operation of
such a MIMO radar required the distribution of a common high-frequency car-
rier signal or other elaborate synchronization solutions. This work introduces
a system concept and prototypical realization of an incoherent MIMO radar
network based on integrated radar sensors without wired high-frequency links.
The network simultaneously performs monostatic and bistatic measurements
between all pairs of sensor nodes, using independently generated Frequency-
Modulated Continuous-Wave (FMCW)-modulated transmit signals with fixed
frequency offsets.
In addition to optimum parametrization of the network, the complete signal
processing chain for the operation of this network is presented. First, co-
herency is established by estimating the unknown time, frequency, and phase
offsets, yielding high-precision range and speed measurements. Subsequently,
these estimates are used to distinguish the contour of targets or estimate their
position using multilateration algorithms. The latter include bistatic measure-
ments of both range and speed, which is shown to improve the precision of
target position estimates by a factor of 10 with the used system parameters.
The performance limits of this approach considering random and systematic
nonidealities are determined by deducing them from fundamental stochastic
processes. They are verified with a newly introduced computationally efficient
simulation which regards the correlation in the stochastic processes. This re-
veals strict requirements for the purity of the independently synthesized signals
to allow bistatic measurements.
The prototypical realization of the network with three sensor nodes using
integrated radar transceivers operating at 122GHz proves the feasibility of
the approach. With chirp sequences of 30 ramps of 1ms length and 1GHz
bandwidth, unambiguous range precisions of < 1mm are achieved using a small
metal panel at 1m distance. The reconstructed phases exhibit a precision of
< 0.1rad, allowing ambiguous range precisions of < 10µm and speed precisions
of < 1mm/s. The attainable high precision and comparatively low realization
effort make the proposed network approach a favorable design for a wide range
of applications.
Date created
2020
Subject headings
[GND]: FMCW-Radar | Netzwerk | MIMO[LCSH]: Radar
[Free subject headings]: Network | Incoherent | Cooperative | Distributed | FDM
[DDC subject group]: DDC 620 / Engineering & allied operations
Metadata
Show full item recordDOI & citation
Please use this identifier to cite or link to this item: http://dx.doi.org/10.18725/OPARU-34323
Frischen, Andreas (2021): MIMO radar networks with incoherent sensor nodes. Open Access Repositorium der Universität Ulm und Technischen Hochschule Ulm. Dissertation. http://dx.doi.org/10.18725/OPARU-34323
Citation formatter >