In (1), [n.sub.t] is the
AWGN term with zero mean and variance of [[sigma].sup.2].
In this work, we discuss the watermark error probability under the presence of
AWGN as follows.
Proposed work is tested on various types of noises like White Gaussian Noise (WGN), Adaptive White Gaussian Noise (
AWGN) etc.
A series of computer simulation tests using C programming language have been carried out on the system in Figure 1 with three types of detectors, DR1, DR2 and DR3, to determine their relative tolerance to
AWGN when operating over ADPCM link in cascade with telephone channel.
Figure 4 shows simulation snapshot of two targets in an
AWGN channel.
The output of BPSK is provide to
AWGN white noise channel, where the SNR parameter is varied from 40dB to -30dB.
where w(n) is
AWGN and [R] denotes circular convolution.
In the channel parameters [[alpha].sub.n,1] = 1 and [[alpha].sub.n,2] = 0, the BER of the MISO-SRMR-DCSK system under the
AWGN channel can be expressed as
where h [n] and [z.sub.1] [n] and [z.sub.2] [n] are the channel impulse response and the
AWGN signal added on the 1st and the 2nd subframes, respectively.
Let n ~ CN(0, [R.sub.N]) represent the
AWGN. [R.sub.N] denotes the covariance matrix of noise.
If a transmitted symbol does not interfere with the jamming signal and the
AWGN channel is assumed, then the probability density functions (PDFs) of [y.sub.0] and [y.sub.j], j [member of] {1, ..., M - 1}, are derived as follows [24]:
Caption: Figure 5: (a) Recovered image after
AWGN attack.