Research On Dirty Paper Coding For Radio Frequency Watermarking

In recent years,the physical layer security technology has been focused on relevant scholars who have paid most of attention on radio frequency(RF)watermarking of information hiding.Information hiding technology has been a hot research topic,and the digital watermarking has become the most important part of it.This article pays attention to RF watermarking and mainly studies the hidden information transmission technology in RF signals,which is called the RF watermarking or the physical layer watermarking.Dirty paper channel is interfered by two additive noises,one of which is known to transmitters and the other is unknown to both transmitters and receivers.The additive noise known to the transmitters is called disturbance,and the additive noise unknown to both the transmitters and receivers is called channel noise.Because dirty paper coding(DPC)has been widely used in the digital watermarking and other fields,it's of great significance to study the theory of DPC for RF watermarking.This paper mainly studies the transmission schemes based on DPC,embeds RF watermarking to the disturbance signals at the transmitters,extracts the RF watermarking and demodulates the original disturbance signals at the receivers.Firstly,this paper based on additive white Gaussian noise(AWGN)channel and slow fading channel respectively proposes the three DPC algorithms called relevant coding,constant coding and symmetric relevant coding which mainly include the signal modulation algorithms,the related watermarking demodulation algorithms and the related disturbance demodulation algorithms.Then it also makes a theoretical and quantitative analysis of reliability,imperceptibility and availability which are three indicators of coding performance through the related formulas derived from the signal modulation and demodulation algorithms.Reliability is measured by the bit-error-rate(BER)of the watermarking bits,and imperceptibility is measured by the BER of the disturbance bits,and availability is measured by the channel capacity.Thetheoretical analysis and simulation results show that symmetric relevant coding has the highest reliability,imperceptibility and availability.The simulation results prove that constant coding has the second-highest reliability,imperceptibility and availability.And relevant coding has the lowest reliability,imperceptibility and availability.Finally,coding performance based on DPC is established on the software platform.The key parameters of affecting DPC performances are tested,including watermarking-to-noise ratio(WNR),disturbance-to-noise ratio(DNR)and disturbance-to-watermarking ratio(DWR).And the practice is consistent with the expectation.To summarize,in practical applications,we should consider the impact of DPC performance,reasonably configure related parameters such as WNR,DNR and DWR,and optimize coding performance.