We have developed a controlled Monte Carlo (CMC) method to calculate the time-dependent transmittance of light through a thick tissue, especially for evaluation of the contribution from early arriving photons. Quasi-straightforward propagating trajectories are favoured according to a selection mechanism, so adequate trajectories of interest can reach the detector, improving the statistics dramatically. Simulations were conducted for tissue models with a thickness of 3-5 cm, and with optical properties similar to human breast tissue. Temporal profiles of early transmittance were obtained with satisfactory convergence. In addition, comparison was made with the conventional Monte Carlo approach to verify our scheme when applied to cases of optically thin tissues.

A novel miniature microstrip-fed multiband antenna for wireless local area network (WLAN) and X-band satellite communication applications is presented in this paper. The proposed antenna consists of two arc-shaped strips, dual inverted L-shaped parasitic stubs, and a partial ground plane. The proposed antenna can excite multi-resonant modes while achieving a compact size of 18 × 34.5 × 0.8 mm 3. The measurement results show that −10 dB impedance bandwidths are 290 MHz (2.28-2.57 GHz), 1.27 GHz (5.0-6.27 GHz), and 850 MHz (7.11-7.96 GHz), which can cover the entire operation frequencies of WLAN (2.48-2.4835 GHz, 5.15-5.875 GHz) and X-band satellite communication system (7.25-7.75 GHz) applications.

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Abstract-A compact coplanar waveguide fed multiband antenna is proposed and investigated. The proposed antenna consists of a rectangular radiating patch and dual meander strips with a defected ground plane. The size of the fabricated prototype is 28.3 × 24 × 1.59 mm 3 . The proposed antenna radiates at three different resonant modes, which cover 2.29-2.63 GHz, 3.26-3.96 GHz, and 4.97-6.10 GHz. The proposed antenna can be used for TD-LTE 2300/2500 (2.305-2.4 GHz), WLAN (2.4-2.4835 GHz and 5.15-5.875 GHz) and WiMAX (2.3-2.4 GHz and 3.3-3.7 GHz) applications. The proposed antenna exhibits an omnidirectional radiation pattern in the H-plane and a dipole-like radiation pattern in the E-plane. The measured peak gains are 2.64/4.48/6.08 dBi at 2.4/3.5/5.5 GHz operating frequency bands, respectively.

A coplanar waveguide- (CPW-) fed dual-band multiple-input multiple-output (MIMO) antenna for 2.45/5.5 GHz wireless local area network (WLAN) applications is presented in this paper. The presented MIMO antenna consists of two identical trapezoidal radiating elements which are perpendicular to each other. The size of the entire MIMO antenna is 50 × 50 × 1.59 mm3, which is printed on a FR4 substrate. The measured impedance bandwidth of the proposed antenna is 2.25–3.15 GHz and 4.89–5.95 GHz, which can cover IEEE 802.11 a/b/g frequency bands. A rectangular microstrip stub is introduced to achieve a good isolation which is less than −15 dB in both operation frequency bands. The measured peak gain is 5.59 dBi at 2.45 GHz and 5.63 dBi at 5.5 GHz. The measured antenna efficiency is 77.8% and 80.4% in the lower and higher frequency bands, respectively. The ECC values at the lower and higher frequencies are lower than 0.003 and 0.01, respectively.