Real time spectrum sensing with certain accuracy plays a key role in cognitive radio. Cyclostationary feature is used for spectrum sensing in this paper. Usually, cyclostationary feature detection requires high computation complexity, in this paper we analyze the performance of some frequencies and cycle frequencies for detection according to the licensed… (More)
This paper presents a two-step strategy to provide a quality-predictable image reconstruction. A Pre-computed Back Projection based Penalized-Likelihood (PPL) method is proposed in the strategy to generate consistent image quality. To solve PPL efficiently, relaxed Ordered Subsets (OS) is applied. A training sets based evaluation is performed to quantify… (More)
In this paper, we present a novel statistical reconstruction method based on Compton noise suppression for Digital Breast Tomosynthesis. The physical modeling for X-ray's interaction with tissues was investigated. A Compton noise based statistical model with a conjugate prior was introduced. Results from our proposed method, Backprojection (BP) method,… (More)
Spectrum sensing is one of the most challenging problems in cognitive radio, spectrum sensing includes the detection of primary users and secondary users which are in other cognitive networks in the same region, but most of papers about spectrum sensing only consider the primary userspsila detection. In this paper, we consider the detection of secondary… (More)
Cognitive radio is an intelligent wireless technology that increases the spectrum efficiency for its usage in applications. CR enriches wireless technology by utilizing the spectrum holes in order to provide high order quality service to users and to minimize the interference that can occur in the network. The work that has to be proposed we will uses two… (More)
Digital tomosynthesis is an innovative imaging technology for early breast cancer detection by providing three-dimensional anatomical information with fast image acquisition and low-dose radiation. Most of current breast tomosynthesis systems utilize a design where a single x-ray tube moves along an arc above objects over a certain angular range. The… (More)
Spectrum sensing is a key of technology of cognitive radio. Based on differences between distribution of a modulated signal and a noise, in this paper, a spectrum sensing method is proposed. Simulations based on BPSK, QPSK, 16QAM and 64QAM show that our proposed method has low complexity of computation and good performance.