where is the normalized energy consumption with respect to the energy consumption for receiving denoted by and (3).
It can be seen that although the received symbol denoted by "+" has a smaller Euclidean distance to than the point denoted by " ", the latter has increased distances to the decision thresholds of the QPSK constellation (the real and imaginary axes) and therefore is more tolerant to noise and yields more reliable detection.
At the receiver, after analog-to-digital conversion, the discrete time received signal, denoted with y, is defined as y = ∑ s = 0 P - 1 h CH ( s, ℓ ) x ( ℓ - s ) + η , ℓ ∈ Z, (2).
Assume there are N available received samples, denoted as r= [ r1,⋯,r⋯,r N ].
The received image denoted as, could be the watermarked image or the watermarked image altered by attacks.
Therefore, the received signal, denoted by y(n), is processed by an analysis FB whose k th sub-channel output is b k Nn = ∑ m ∈ Z y m h k Nn − m = U k Nn, β + I k Nn, β + η k Nn, β. (3).
As illustrated in Fig. 3, this acknowledgement is sent, by the base station, after a fixed receive delay denoted T d.
As a result of playing one of the strategies, the th user will receive payoff, denoted hereafter.
The instantaneous post-detection SNR of Alamouti's STBC scheme with two transmit and N receive antennas, denoted as γ S, is given by γ S = γ ∑ i = 1 N h i, 1 2 + h i, 2 2 (53).
In this setup, a BS with a total transmit power P T and equipped with N T transmit antennas provides service to N m active MS, each equipped, without loss of generality, with an equal number of receive antennas, denoted by N R. Figure 1 System model for cross-layer downlink scheduling and resource allocation over a OFDMA wireless network.
