Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation system. The transmission channel is divided into a number of subchannel in which each subchannel is assigned a subcarrier. Conventional OFDM systems use IFFT and FFT algorithms at the transmitter and receiver respectively to multiplex the signals and transmit them simultaneously over a number of subcarriers. The syst...

in this research the thin layer drying behavior of apricot (cv. ghavami and nasiry) at temperatures of drying air of 40, 50, 60 and 70 ºc and at drying air velocity of 2 ms-1 was studied. in order to select the best drying curve equation, 9 different thin layer drying models were fitted to the experimental data and were compared according to their coefficient of determination (r2), reduced chi-...

Dear Prof. Mozdarani,I would like to discuss about some important aspects regarding the article published in, "Iran. J. Radiat. Res., 2012 10(2): 89-94“ with title of “Patient doses from X-ray computed tomography examinations by a single-array detector unit: Axial versus spiral mode" by Ghavami et al. (1), so according to journal policy and in suitable manner please ask the authors to rep...

This paper investigates the capacity and capacity per unit cost of Gaussian multiple-access channel (GMAC) with peak power constraints. We first devise an approach based on Blahut-Arimoto Algorithm to numerically optimize the sum rate and quantify the corresponding input distributions. The results reveal that in the case with identical peak power constraints, the user with higher SNR is to have...

Wang et al. have provided new and novel evidence about the importance of using α-fetoprotein (ALP) and glypican-3 (GPC-3) mRNA detection in peripheral blood of the patients with hepatocellular carcinoma (HCC) recurrence after ortothopic liver transplantation (OLT) (1). HCC keeps on as major universal health apprehension ensuing in more than 1 million caner associated deaths annually (2, 3). The...

in this research, chilling and heating requirements of six local cultivars of apricot (jafari, ghavami, jahangiri, khiari, khiveaee and rajabali) were evaluated under field and lab conditions. under lab condition, ‘rajabali’ and in some extent ‘johangiri’ began flowering after 500 hours in 4°c. other cultivars except ‘khiari’ flowered at 750 h. ‘khiari’ flowered at 1000 h. in field, due to litt...

Ultra Wideband (UWB) communication technology has attracted considerable attention by researchers in recent years because of its appealing features and its several applications it offers in many areas (Win & Scholtz, 1998; Fontana, 2007; Ghavami et al, 2007). An UWB system is characterised by very short-duration pulses (usually on the order of a nanosecond) with a low duty cycle. It offers low ...