Antenna Solutions for 4G Smartphones in Laser Direct Structuring Technology

Two antenna designs operating in the LTE/4G cellular frequency bands are proposed in this paper. Both designs consist of a driven strip which capacitively excites a parasitic grounded strip for a better matching response around 700 MHz. The antennas are realized using Laser Direct Structuring (LDS) technology on POCAN plastic material with a height of 5 mm above the system Printed Circuit Board. Passive matching circuits are necessary at each antenna’s feed, to match the input impedance to 50 Ohm at the desired operating bands (700-960 MHz and 1.7-2.2 GHz for the first design and 700-960 MHz and 1.7-2.7 GHz for the second). The simulation results are validated through s-parameter and total efficiency measurements. To form a basis for future studies, the effect of the hand and the head of the user are investigated upon the antenna performance

Feasibility study of 4G cellular antennas for eyewear communicating devices

A feasibility study of 4G cellular antennas operating in the LTE, GSM, DCS, PCS, and WLAN2400 standards for wirelessly connected eyewear is presented. The target bands are 700-960 MHz and 1.7-2.7 GHz. The antenna designs are capacitive coupling element types, with simple layout printed on one side of the printed circuit board (PCB) substrate. Three different antennas are examined in terms of obtainable bandwidth potential, reflection coefficient, and specific absorption rate (SAR) values considering two human-head models (SAM and Visible Human). The best antenna is -6 dB matched and has radiation efficiencies around 14% and 36% in respectively low and high frequency bands. Based on simulation data, SAR values could be above the 1-g standards

Feasibility study of 4G cellular antennas for eyewear communicating devices

A feasibility study of 4G cellular antennas operating in the LTE, GSM, DCS, PCS, and WLAN2400 standards for wirelessly connected eyewear is presented. The target bands are 700-960 MHz and 1.7-2.7 GHz. The antenna designs are capacitive coupling element types, with simple layout printed on one side of the printed circuit board (PCB) substrate. Three different antennas are examined in terms of obtainable bandwidth potential, reflection coefficient, and specific absorption rate (SAR) values considering two human-head models (SAM and Visible Human). The best antenna is -6 dB matched and has radiation efficiencies around 14% and 36% in respectively low and high frequency bands. Based on simulation data, SAR values could be above the 1-g standards

MIMO antenna concept for 4G electronic eyewear devices

MIMO antenna concepts for electronic eyewear devices operating in 4G cellular standard are proposed in this paper. Coupling element type antennas and matching circuits are used to obtain a high bandwidth potential for the coverage of the 700-960MHz and 1.7-2.7GHz frequency bands. To obtain a dual-antenna MIMO configuration, two CE type antennas are placed on the two sides of the head, resulting in a very high isolation level thanks to the lossy nature of the human tissues (head). It is shown through simulated 3D radiation patterns that very low envelope correlation coefficients are obtained for this placement. Preliminary SAR simulations show values above the 1g standards

Ball grid array-module with integrated shaped lens for WiGig applications in eyewear devices

A ball grid array-module (BGA-module) incorporating a low-cost shaped dielectric lens is proposed for wireless communications in the 60-GHz WiGig band between a smart eye-wear, where it is integrated and facing a laptop or TV. The module, which is codesigned with a 60-GHz transceiver, consists of two separate identical antennas for transmitting (Tx) and receiving (Rx). The in-plane separation of these elements is 6.9 mm both being offset from the lens focus. This poses a challenge to the lens design to ensure coincident beam pointing directions for Rx and Tx. The shaped lens is further required to narrow the angular coverage in the elevation plane and broaden it in the horizontal plane. A 3-D-printed eyewear frame with an integrated lens and a recess for proper BGA-module integration is fabricated in ABS-plastic material. Measurements show a reflection coefficient below -12 dB in the 57-66 GHz band. A maximum gain of 11 dBi is obtained at 60 GHz, with 24 degrees and 96 degrees beamwidth at 5-dBi gain, respectively, in the vertical and horizontal planes. The radiation exposure is evaluated for a homogeneous SAM head phantom and a heterogeneous visible human head. The simulated power density values for both models are found to be lower than the existing standards

Evidence for a narrow dip structure at 1.9 GeV/c2^2 in 3π+3π−3\pi^+ 3\pi^- diffractive photoproduction

A narrow dip structure has been observed at 1.9 GeV/c$^2$ in a study of diffractive photoproduction of the $~3\pi^+3\pi^-$ final state performed by the Fermilab experiment E687.Comment: The data of Figure 6 can be obtained by downloading the raw data file e687_6pi.txt. v5 (2nov2018): added Fig. 7, the 6 pion energy distribution as requested by a reade

Search for Chargino-Neutralino Associated Production at the Fermilab Tevatron Collider

We have searched in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.8 TeV for events with three charged leptons and missing transverse energy. In the Minimal Supersymmetric Standard Model, we expect trilepton events from chargino-neutralino (\chione \chitwo) pair production, with subsequent decay into leptons. We observe no candidate $e^+e^-e^\pm$, $e^+e^-\mu^\pm$, $e^\pm\mu^+\mu^-$ or $\mu^+\mu^-\mu^\pm$ events in 106 pb$^{-1}$ integrated luminosity. We present limits on the sum of the branching ratios times cross section for the four channels: \sigma_{\chione\chitwo}\cdot BR(\chione\chitwo\to 3\ell+X) 81.5 \mgev\sp and M_\chitwo > 82.2 \mgev\sp for $\tan\beta=2$, $\mu =-600$~\mgev\sp and M_\squark= M_\gluino.Comment: 9 pages and 3 figure

Search for a Fourth-Generation Quark More Massive than the Z0 Boson in ppbar Collisions at sqrt(s) = 1.8 TeV

We present the results of a search for pair production of a fourth-generation charge -1/3 quark (b') in sqrt(s)=1.8 TeV ppbar collisions using 88 pb^(-1) of data obtained with the Collider Detector at Fermilab. We assume that both quarks decay via the flavor-changing neutral current process b' -> bZ and that the b' mass is greater than m_Z + m_b. We studied the decay mode b'b'bar -> ZZ b bbar where one Z0 decays into e^+e^- or mu^+ mu^- and the other decays hadronically, giving a signature of two leptons plus jets. An upper limit on the cross section of ppbar -> b'b'bar times [BR (b' -> bZ)]^2 is established as a function of the b' mass. We exclude at 95% confidence level a b' quark with mass between 100 and 199 GeV/c^2 for BR(b' -> bZ) = 100%.Comment: 12 pages, 2 figures, submitted to Phys. Rev. Letters on 9/12/9

Production of Y(1S) Mesons from chib Decays in pp(bar) Collisions at sqrt(s)=1.8 TeV

We have reconstructed the radiative decays $\chi_{b}(1P) \to \Upsilon(1S) \gamma$ and $\chi_{b}(2P) \to \Upsilon(1S) \gamma$ in $p \bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV, and measured the fraction of $\Upsilon(1S)$ mesons that originate from these decays. For $\Upsilon(1S)$ mesons with $p^{\Upsilon}_{T}>8.0$ GeV/$c$, the fractions that come from $\chi_{b}(1P)$ and $\chi_{b}(2P)$ decays are $(27.1\pm6.9(stat)\pm4.4(sys))$ and $(10.5\pm4.4(stat)\pm1.4(sys))$, respectively. We have derived the fraction of directly produced $\Upsilon(1S)$ mesons to be $(50.9\pm8.2(stat)\pm9.0(sys))$.Comment: 13 Pages, 2 figure