MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints

Khaled Alhujaili, Vishal Monga, Muralidhar Rangaswamy

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The capability of Multiple-Input Multiple-Output (MIMO) radar systems to adapt waveforms across antennas allows flexibility in transmit beampattern design. In cognitive radar, a popular cost function is to minimize deviation against an idealized beampattern (which is arrived at with knowledge of the environment). The optimization of transmit beampattern becomes particularly challenging in the presence of practical constraints on the transmit waveform. In this work, we study two important but difficult non-convex constraints: constant modulus and orthogonality of waveform code across transmit antennas. Individually, incorporating these constraints continues to be challenging and they have rarely been jointly studied because each set is individually a (non-convex) manifold. We develop a new approach by leveraging the theory of optimization over manifolds: we derive a new projection, descent and retraction (PDR) update strategy that allows for monotonic cost function improvement while maintaining feasibility over the complex circle manifold (constant modulus set). The approach allows a tractable extension to incorporate orthogonality as a penalty term with the cost function. We provide analytical guarantees of monotonic cost function improvement along with proof of convergence. Experimentally, we show that PDR can outperform state of the art wideband beampattern design methods while being computationally tractable. Robustness to target direction mismatch (enabled by orthogonal waveforms) is also demonstrated.

Original languageEnglish (US)
Title of host publicationConference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018
EditorsMichael B. Matthews
PublisherIEEE Computer Society
Pages1899-1904
Number of pages6
ISBN (Electronic)9781538692189
DOIs
StatePublished - Feb 19 2019
Event52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018 - Pacific Grove, United States
Duration: Oct 28 2018Oct 31 2018

Publication series

NameConference Record - Asilomar Conference on Signals, Systems and Computers
Volume2018-October
ISSN (Print)1058-6393

Conference

Conference52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018
CountryUnited States
CityPacific Grove
Period10/28/1810/31/18

Fingerprint

Cost functions
Radar
Antennas
Radar systems

All Science Journal Classification (ASJC) codes

  • Signal Processing
  • Computer Networks and Communications

Cite this

Alhujaili, K., Monga, V., & Rangaswamy, M. (2019). MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints. In M. B. Matthews (Ed.), Conference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018 (pp. 1899-1904). [8645373] (Conference Record - Asilomar Conference on Signals, Systems and Computers; Vol. 2018-October). IEEE Computer Society. https://doi.org/10.1109/ACSSC.2018.8645373
Alhujaili, Khaled ; Monga, Vishal ; Rangaswamy, Muralidhar. / MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints. Conference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018. editor / Michael B. Matthews. IEEE Computer Society, 2019. pp. 1899-1904 (Conference Record - Asilomar Conference on Signals, Systems and Computers).
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Alhujaili, K, Monga, V & Rangaswamy, M 2019, MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints. in MB Matthews (ed.), Conference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018., 8645373, Conference Record - Asilomar Conference on Signals, Systems and Computers, vol. 2018-October, IEEE Computer Society, pp. 1899-1904, 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018, Pacific Grove, United States, 10/28/18. https://doi.org/10.1109/ACSSC.2018.8645373

MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints. / Alhujaili, Khaled; Monga, Vishal; Rangaswamy, Muralidhar.

Conference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018. ed. / Michael B. Matthews. IEEE Computer Society, 2019. p. 1899-1904 8645373 (Conference Record - Asilomar Conference on Signals, Systems and Computers; Vol. 2018-October).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Alhujaili K, Monga V, Rangaswamy M. MIMO Radar Beampattern Design under Joint Constant Modulus and Orthogonality Constraints. In Matthews MB, editor, Conference Record of the 52nd Asilomar Conference on Signals, Systems and Computers, ACSSC 2018. IEEE Computer Society. 2019. p. 1899-1904. 8645373. (Conference Record - Asilomar Conference on Signals, Systems and Computers). https://doi.org/10.1109/ACSSC.2018.8645373