Title :
The dependence of the thumbtack shape of the auto-ambiguity of frequency-hop waveforms on the number of hops and time-bandwidth product
Author :
Taylor, Ken ; Rickard, Scott ; Drakakis, Konstantinos
Author_Institution :
Complex & Adaptive Syst. Lab., Univ. Coll. Dublin, Dublin, Ireland
Abstract :
In this work we consider the impact of the number of hops of a frequency hopped code on the autocorrelation surfaces it produces. First, we review two common choices for the number of hops, namely the `Minimal Sidelobe Region´ (MSR) choice, and the `Nyquist´ choice. The MSR method ensures that peaks in the sidelobe region are small, while the Nyquist method exhibits much cleaner center region behavior. We then propose two new methods for choosing the length of the frequency hopped code. The first, named `Minimize Maximal Sidelobe´ (MMS), attempts to minimize sibelobes in both regions, and the second, `Minimize Maximum Peak Sidelobe´ (MMPS), focuses on center region behavior. We then compare the results to the two existing methods.
Keywords :
Nyquist criterion; codes; frequency hop communication; Nyquist method; autoambiguity; frequency hopped code; minimal sidelobe region choice; minimize maximal sidelobe; minimize maximum peak sidelobe; thumbtack shape; time-bandwidth product; Correlation; Encoding; Equations; Least squares approximation; Sonar; Surface waves; Time frequency analysis; Correlation; Frequency-Hop; Permutation Matrices; Time-Bandwidth;
Conference_Titel :
Digital Signal Processing Workshop and IEEE Signal Processing Education Workshop (DSP/SPE), 2011 IEEE
Conference_Location :
Sedona, AZ
Print_ISBN :
978-1-61284-226-4
DOI :
10.1109/DSP-SPE.2011.5739179