Wireless networks suffer from battery discharging specially in cooperative communications when multiple relays have an important role but they are energyconstrained. To overcome this problem, energy harvesting from Radio Frequency signals is applied to charge the node battery. These intermediate nodes have the ability to harvest energy from the source signal and use the harvested energy to transmit information to the destination. Simultaneous energy harvesting and data transmission can be done in multi-relay systems. Each relay dedicates a part of time or power for energy harvesting, and the remainder part is devoted for data transmission. Based on time or power division, 2 relaying protocols known as time switching based relaying protocol or power splitting based relaying protocol exist. These 2 protocols can also be applied in delay-limited and delay-tolerant transmission systems. The previous works have assumed a single relay or single antenna for energy harvesting, but in this paper, the proposed method is concentrated on improving the throughput by using multiple antennas in multi-relay system. Two strategies of selecting the signal of multiple antennas for transmission known as maximum ratio transmit and Antenna selection has been used in this paper.Maximum ratio transmit combines the signals of antennas but Antenna selection selects the antenna with maximum signal-to-noise ratio. According to our simulation results, when using multi-antenna relays, ability of energy harvesting is increased compared with single-relay or single-antenna system and thus the system performance will be improved considerably. Also, maximum ratio transmit method has better performance compared with Antenna Selection one.

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Breast cancer is the most common type of cancer in females. In many cases, the mortality rate can be drastically lowered if the disease is detected early. Due to its safety and lack of risk to the patient, microwave breast imaging is considered a potential replacement for mammography. This paper presents a breast cancer detection approach based on the Multi-Variate and Multi-Dimensional Constant False Alarm Rate (MVMD-CFAR) method. This method has several advantages over mammography using x-rays, including increased patient comfort and lower costs. On an open-source experimental database derived from the University of Manitoba Microwave Mammography Dataset UM-BMID, the performance of the (2D-CFAR) method is evaluated by examining the available data set for breast microwave sensing. We segregate infected and healthy samples and assessed the probability density function PDF for pictures of normal and malignant tissue. The third dimension of the algorithm is the image's color data, which comprises three variables (three colors). Initial testing show that the MVMD-CFAR detector is highly effective, with a detection probability of 97.4% and a false alarm probability of 10%. However, a few challenges must be overcome before this imaging technique can reach its full potential and be implemented in clinical settings.