1 research outputs found
Waveform Design and Accurate Channel Estimation for Frequency-Hopping MIMO Radar-Based Communications
Frequency-hopping (FH) MIMO radar-based dual-function radar communication
(FH-MIMO DFRC) enables communication symbol rate to exceed radar pulse
repetition frequency, which requires accurate estimations of timing offset and
channel parameters. The estimations, however, are challenging due to unknown,
fast-changing hopping frequencies and the multiplicative coupling between
timing offset and channel parameters. In this paper, we develop accurate
methods for a single-antenna communication receiver to estimate timing offset
and channel for FH-MIMO DFRC. First, we design a novel FH-MIMO radar waveform,
which enables a communication receiver to estimate the hopping frequency
sequence (HFS) used by radar, instead of acquiring it from radar. Importantly,
the novel waveform incurs no degradation to radar ranging performance. Then,
via capturing distinct HFS features, we develop two estimators for timing
offset and derive mean squared error lower bound of each estimator. Using the
bounds, we design an HFS that renders both estimators applicable. Furthermore,
we develop an accurate channel estimation method, reusing the single hop for
timing offset estimation. Validated by simulations, the accurate channel
estimates attained by the proposed methods enable the communication performance
of DFRC to approach that achieved based on perfect timing and ideal knowledge
of channel.Comment: 14 pages, 10 figures, submitted to IEEE journa