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The microwave dielectric properties of (Mg((1-x))Co(x))(2)SnO(4) ceramics were examined with a view to their exploitation for mobile communication. The (Mg((1-x))Co(x))(2)SnO(4) ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the (Mg((1-x))Co(x))(2)SnO(4) ceramics revealed no significant variation of phase with sintering temperatures. Specimens were not single-phase materials; small amounts of MgO and SnO(2) as the second phases were observed in all specimens. A dielectric constant (ε(τ)) of 8.8, a quality factor (Q × f) of 110800 GHz (at 16.4 GHz), and a temperature coefficient of resonant frequency (τ(f)) of -66 ppm/°C were obtained for(Mg(0.93)Co(0.07))(2)SnO(4) ceramics that were sintered at 1550°C for 4 h. The proposed dual-band co-planar waveguide (CPW)-fed inverted-E-shaped monopole covered the industrial, scientific, medical (ISM), high-performance radio local area network (HIPERLAN), and unlicensed national information infrastructure (UNII) bands. A 13.62% bandwidth (return loss <;10 dB) of 2.43 GHz, and a 20.69% bandwidth (return loss <;10 dB) of 5.38 GHz was successfully achieved.

The microwave dielectric properties of La2MoO6 ceramics were investigated in preparation for their application in mobile communication. La2MoO6 ceramics were prepared by the conventional solid-state method under varied sintering conditions. The X-ray diffraction peaks of La2MoO6 ceramic did not vary significantly with sintering conditions. The average grain size of La2MoO6 ceramics increased with increasing the sintering temperature and duration. The maximum density of 5.67 g/cm3, the dielectric constant ( ε r ) of 14.1, the quality factor (Q × f) of 68,000 GHz, and the temperature coefficient of resonant frequency ( τ f ) of −56 ppm/°C had been attained when La2MoO6 ceramics that sintered at 1300 °C for 4h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Nd(Ti0.5Mo0.5)O4 ceramics are examined, considering their application in 5G mobile communication. A maximum density of 5.79 g/cm3 is obtained for the Nd(Ti0.5Mo0.5)O4 ceramics, sintered at 1425 °C for 4 h. The ceramic's relative dielectric constant, unloaded quality factor, and temperature coefficient of the resonant frequency are 18.5, 29300 GHz, and 35 ppm/°C, respectively. The measurement results of the patch antenna application in 5G FR2 band are presented. A 14.5% bandwidth (return loss < 6 dB) of 29.6 GHz was implemented successfully for application in 5G n261 band. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Ba2Mg1–xZnxWO6 ceramics were examined with a view to their exploitation for mobile communication. The Ba2Mg1–xZnxWO6 ceramics were prepared by the conventional solid-state method. The X-ray diffraction patterns of the Ba2Mg1–xZnxWO6 ceramics revealed that Ba2MgWO6 is the main crystalline phase, which is accompanied by small amounts of BaWO4 and Ba2WO5 as secondary phases. A maximum density of 6.72 g/cm3 was obtained for Ba2Mg0.95Zn0.05WO6 ceramic, sintered at 1650 °C for 4 h. Dielectric constant ( ε r ) of 17.9, quality factor (Q × f) of 157,000 GHz, and temperature coefficient of resonant frequency ( τ f ) of −35 ppm/°C were obtained for Ba2Mg0.95Zn0.05WO6 ceramics that were sintered at 1650 °C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Ba2Mg1–xZnxWO6 ceramics were examined with a view to their exploitation for mobile communication. The Ba2Mg1–xZnxWO6 ceramics were prepared by the conventional solid-state method. The X-ray diffraction patterns of the Ba2Mg1–xZnxWO6 ceramics revealed that Ba2MgWO6 is the main crystalline phase, which is accompanied by small amounts of BaWO4 and Ba2WO5 as secondary phases. A maximum density of 6.72 g/cm3 was obtained for Ba2Mg0.95Zn0.05WO6 ceramic, sintered at 1650 °C for 4 h. Dielectric constant ( ε r ) of 17.9, quality factor (Q × f) of 157,000 GHz, and temperature coefficient of resonant frequency ( τ f ) of −35 ppm/°C were obtained for Ba2Mg0.95Zn0.05WO6 ceramics that were sintered at 1650 °C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Nd(Ti0.5W0.5)O4 ceramics were examined with a view to their application in mobile communication. The Nd(Ti0.5W0.5)O4 ceramics were prepared using the conventional solid-state method. A maximum density of 6.65 g/cm3 was obtained for the Nd(Ti0.5W0.5)O4 ceramic, sintered at 1500 °C for 4 h. Dielectric constants ( ε r ) of 15.4–19.4 and quality factor (Q × f) of 3,600–11,100 GHz were obtained at sintering temperatures in the range 1425–1525 °C for 4 h. A Nd(Ti0.5W0.5)O4 ceramic that was sintered at 1500 °C for 4 h had a dielectric constant ( ε r ) of 19.4, a quality factor (Q × f) of 11,100 GHz, and a temperature coefficient of resonant frequency ( τ f ) of −48 ppm/°C. The hybrid dielectric resonator antenna consisted of a cylindrical high dielectric constant dielectric resonator and a rectangular slot was implemented. The hybrid dielectric resonator antenna had two resonant frequencies. The lower and higher resonant frequencies were associated with the rectangular slot and dielectric resonator, respectively. Parametric investigation was carried out using simulation software. The proposed hybrid dielectric resonator antenna had good agreement between the simulation results and the measurement results. The proposed hybrid dielectric resonator antenna has frequencies cover sub-6 GHz band and LTE band 3. A 10.2% bandwidth (return loss <10 dB) of 1.77 GHz, and a 9.9% bandwidth (return loss <10 dB) of 3.43 GHz was implemented successfully for application in sub-6 GHz band and LTE band 3. [ABSTRACT FROM AUTHOR]

The series of La(Mg0.5−xNixSn0.5)O3 microwave ceramics were investigated for application in sub-6 GHz patch array antenna. The microwave dielectric characteristics of La(Mg0.5−xNixSn0.5)O3 ceramics are determined using X-ray diffraction patterns, Rietveld refinement, and Raman spectra. As the degree of substitution of Ni2+ increases, the position of the A1g(O) Raman mode shifts toward a higher frequency. The La(Mg0.45Ni0.05Sn0.5)O3 exhibits a minimum full width at half maximum for the A1g(O) Raman vibration mode. At x = 0.05, a permittivity of 19.8 and a quality factor (Q × f) of 104,000 GHz were achieved with a temperature coefficient at the resonant frequency (TCF) of − 87.9 ppm/°C. The proposed sub-6 GHz 2 × 2 patch array antenna has frequencies cover sub-6 GHz band, LTE band 42, and LTE band 43. A 10 dB return loss with bandwidth 848 MHz (3114–3962 MHz) was successfully achieved. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Nd(Ti0.5−xZrx)W0.5O4 ceramics were examined with a view to their application in mobile communication. The Nd(Ti0.5−xZrx)W0.5O4 ceramics were prepared using the conventional solid-state method. Dielectric constants (εr) of 15.4–19.4 and quality factor (Q × f) of 3600–11,100 GHz were obtained for NdTi0.5W0.5O4 ceramics at sintering temperatures in the range 1425–1525 °C for 4 h. A maximum density of 6.68 g/cm3 was obtained for the Nd(Ti0.47Zr0.03W0.5)O4 ceramic, sintered at 1500 °C for 4 h. A Nd(Ti0.47Zr0.03W0.5)O4 ceramic that was sintered at 1500 °C for 4 h had a dielectric constant (εr) of 19.8, a quality factor (Q × f) of 17,300 GHz, and a temperature coefficient of resonant frequency (τf) of − 54 ppm/°C. The proposed patch antenna sensor had a sensitivity of 0.112 MHz/°C. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of ZnNi(TiSn)O ceramics were examined with a view to their exploitation for mobile communication. The ZnNi(TiSn)O ceramics were prepared by the conventional solid-state method. The diffraction peaks of ZnNi(TiSn)O ceramics shifted to lower angles as x increased. The unit cell volumes of ZnNi(TiSn)O ceramics increased from 599.592 to 616.534 Å as x increased from 0 to 0.5. The average grain size of the ZnNi(TiSn)O ceramics increased from 19.84 to 20.21 μm as x increased from 0 to 0.05 and decreased from 20.21 to 12.57 μm as x increased from 0.05 to 0.5. Dielectric constant ( ε ) of 16.7, quality factor ( Q × f) of 73,600 GHz, and temperature coefficient of resonant frequency ( τ ) of −45 ppm/ °C were obtained for ZnNi(TiSn)O ceramics that were sintered at 1550 °C for 2 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of ZnNiTiO ceramics were investigated with a view to the use of such ceramics in mobile communication. ZnNiTiO ceramics were prepared using the conventional solid-state method with various sintering temperatures and sintering times. A maximum relative density of 97.20 % was obtained by sintering ZnNiTiO ceramic at 1550 °C for 2 h. Dielectric constants ( ɛ ) of 16.5-17.1 and a quality factor ( Q × f) of 26,000-31,700 GHz were obtained at sintering temperatures in the range 1450-1600 °C for 2 h. Dielectric constants ( ɛ ) of 17.0-17.1 and a quality factor ( Q × f) of 21,000-31,700 GHz were obtained at sintering times in the range 1-4 h at a sintering temperature of 1550 °C. A dielectric constant ( ɛ ) of 17.1, a quality factor ( Q × f) of 31,700 GHz, and a temperature coefficient of resonant frequency ( τ ) of −46 ppm/°C were obtained when ZnNiTiO ceramics were sintered at 1550 °C for 2 h. [ABSTRACT FROM AUTHOR]

Dielectric properties of BaMgZnWO ceramics at microwave frequency were examined with a view to their exploitation for mobile communication. The BaMgZnWO ceramics were prepared by the conventional solid-state method. The X-ray diffraction patterns of the BaMgZnWO ceramics revealed that BaMgZnWO is the main crystalline phase, which is accompanied by small amounts of BaWO and BaWO as secondary phases. A maximum density of 6.72 g/cm was obtained for BaMgZnWO ceramic, sintered at 1650 °C for 2 h. Dielectric constant ( ɛ ) of 17.9, quality factor ( Q × f) of 157,000 GHz, and temperature coefficient of resonant frequency ( τ ) of −35 ppm/°C were obtained for BaMgZnWO ceramics that were sintered at 1650 °C for 2 h. [ABSTRACT FROM AUTHOR]

The influence of sintering temperature on the microwave dielectric properties and microstructure of the (1− y )Zn 2 SnO 4 – y Ca 0.8 Sr 0.2 TiO 3 ceramic system were investigated with a view to their application in microwave devices. A (1− y )Zn 2 SnO 4 – y Ca 0.8 Sr 0.2 TiO 3 ceramic system was prepared by the conventional solid-state method. The X-ray diffraction patterns of the 0.85Zn 2 SnO 4 –0.15Ca 0.8 Sr 0.2 TiO 3 ceramic system did not significantly vary with sintering temperature. A dielectric constant of 9.6, a quality factor ( Q × f ) of 15,900 GHz, and a temperature coefficient of resonant frequency of −4 ppm/°C were obtained when the 0.85Zn 2 SnO 4 –0.15Ca 0.8 Sr 0.2 TiO 3 ceramic system was sintered at 1175 °C for 4 h. [ABSTRACT FROM AUTHOR]

In this study, the microwave dielectric properties of Zn 2 SnO 4 ceramics prepared by the conventional solid-state method were investigated for application in mobile communication. Li 2 WO 4 was selected as a liquid sintering aid to reduce the sintering temperature of Zn 2 SnO 4 ceramics. By adding 0.75 wt% Li 2 WO 4 , a dielectric constant of 5.35, a quality factor ( Qf ) of 29,500 GHz, and a temperature coefficient of resonant frequency τ f (−76 ppm/°C) were obtained when Zn 2 SnO 4 ceramics were sintered at 975 °C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Zn 2 SnO 4 ceramics were investigated with a view to the use of such ceramics in mobile communication. Zn 2 SnO 4 ceramics were prepared using the conventional solid-state method with various sintering temperatures. Dielectric constants ( ε r ) of 9.2–10.2 and unloaded quality factor ( Q u × f ) of 12,700–39,000 GHz were obtained at sintering temperatures in the range 1175–1250 °C for 4 h. A maximum relative density of 95.7% was obtained for Zn 2 SnO 4 ceramic, sintered at 1225 °C for 4 h. A dielectric constant ( ε r ) of 10.2, an unloaded quality factor ( Q u × f ) of 39,000 GHz, and a temperature coefficient of resonant frequency ( τ f ) of −84 ppm/°C were obtained when Zn 2 SnO 4 ceramics were sintered at 1225 °C for 4 h. [ABSTRACT FROM AUTHOR]

The influence of Ca0.8Sr0.2TiO3on the microstructures and microwave dielectric properties of Nd0.96Yb0.04(Mg0.5Sn0.5)O3ceramics were investigated by the conventional solid-state method. The X-ray diffraction peaks of (1-y)Nd0.96Yb0.04(Mg0.5Sn0.5)O3-yCa0.8Sr0.2TiO3ceramic system shifted to higher angles as y increased. The dielectric constant increased from 19.5 to 50.6, the quality factor (Q×f) decreased from 117,300 to 49,500 GHz, and the temperature coefficient of resonant frequency (τf) increased from −61 to +57 ppm/°C as y increased from 0 to 0.7 when (1-y)Nd0.96Yb0.04(Mg0.5Sn0.5)O3-yCa0.8Sr0.2TiO3ceramic system sintered at 1600°C for 4h. A 0.4Nd0.96Yb0.04(Mg0.5Sn0.5)O3-0.6Ca0.8Sr0.2TiO3ceramic system that was sintered at 1600°C for 4 h had a dielectric constant of 38.2, a quality factor (Q×f) of 53,500 GHz, and a temperature coefficient of resonant frequency of −3.3 ppm/°C. [ABSTRACT FROM AUTHOR]

In this study, the microwave dielectric properties of Zn 2 SnO 4 ceramics prepared by the conventional solid-state method were investigated for application in mobile communication. ZnO–B 2 O 3 –SiO 2 was selected as a liquid sintering aid to reduce the sintering temperature of Zn 2 SnO 4 ceramics. By adding 3.0 wt.% ZnO–B 2 O 3 –SiO 2 , a dielectric constant of 11.44 and a quality factor ( Q × f ) of 33,000 GHz were obtained when Zn 2 SnO 4 ceramics were sintered at 1075 °C for 4 h. The proposed CPW-fed inverted-U shaped monopole antenna has a 6 dB return loss with bandwidth 204 MHz (2371–2575 MHz) in the lower band, 1520 MHz (3130–4650 MHz) in the middle band, and 460 MHz (5250–5710 MHz) in the higher band. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Zn2(Sn(1−x)Ti x )O4 ceramics were examined with a view to their exploitation for mobile communication. The Zn2(Sn(1−x)Ti x )O4 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the Zn2(Sn0.95Ti0.05)O4 ceramics revealed no significant variation of phase with sintering temperatures. A maximum density of 6.26g/cm3 was obtained for Zn2(Sn0.95Ti0.05)O4 ceramic, sintered at 1225°C for 4h. Dielectric constant (ε r ) of 9.86, quality factor (Q×f) of 76,900GHz, and temperature coefficient of resonant frequency ( ) of −38.6ppm/°C were obtained for Zn2(Sn0.95Ti0.05)O4 ceramics that were sintered at 1225°C for 4h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of Nd(MgBaSn)O ceramics were examined with a view to their exploitation in mobile communication. The Nd(MgBaSn)O ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the Nd(MgBaSn)O ceramics revealed no significant variation of phase with sintering temperatures. A density of 6.91 g/cm, a dielectric constant ( ε) of 19.14, a quality factor ( Q × f) of 97,500 GHz, and a temperature coefficient of resonant frequency ( τ) of −65.4 ppm/°C were obtained for Nd(MgBaSn)O ceramics that were sintered at 1,600 °C for 4 h. [ABSTRACT FROM AUTHOR]

The influence of sintering temperature on the microwave dielectric properties and microstructure of the (1 − y)La(MgSrSn)O-yCaSrTiO ceramic system were investigated with a view to their application in microwave devices. The (1 − y)La(MgSrSn)O-yCaSrTiO ceramic systems were prepared using the conventional solid-state method. The X-ray diffraction patterns of the (1 − y)La(MgSrSn)O-yCaSrTiO ceramic system shifted to higher angle as y increased. A dielectric constant of 41.2, a quality factor ( Q × f) of 56,900 GHz, and a temperature coefficient of resonant frequency of −6 ppm/ °C were obtained when the 0.4La(MgSrSn)O-0.6CaSrTiO ceramic system was sintered at 1,550 °C for 4 h. [ABSTRACT FROM AUTHOR]

This study elucidates the microwave dielectric properties and microstructures of Nd(MgNiSn)O ceramics with a view to their potential for microwave devices. The Nd(MgNiSn)O ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the Nd(MgNiSn)O ceramics revealed no significant variation of phase with sintering temperatures. A dielectric constant ( $$ \varepsilon_{r} $$) of 19.3 and a quality factor ( Q × f) of 93,400 GHz and a temperature coefficient of resonant frequency ( $$ \tau_{f} $$) of −66 ppm/ °C were obtained for Nd(MgNiSn)O ceramics that were sintered at 1,550 °C for 4 h. [ABSTRACT FROM AUTHOR]

Abstract: This study elucidates the microwave dielectric properties and microstructures of Nd(Mg0.5−x Zn x Sn0.5)O3 ceramics for their potential applications in microwave devices. The Nd(Mg0.5−x Zn x Sn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. X-ray diffraction (XRD) patterns of the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics revealed only a slight variation of phase with sintering temperatures. Additionally, a dielectric constant of 19.5, a quality factor (Q × f) of 129,200GHz, and a temperature coefficient of resonant frequency of −66ppm/°C were obtained for Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics sintered at 1500°C for 4h. [Copyright &y& Elsevier]

The influence of B2O3on the microstructure and microwave dielectric properties of the 0.45La0.97Sm0.03(Mg0.5Sn0.5)O3–0.55Ca0.8Sm0.4/3TiO3ceramic system were investigated with a view to their application in microwave devices. A B2O3-doped 0.45La0.97Sm0.03(Mg0.5Sn0.5)O3–0.55Ca0.8Sm0.4/3TiO3ceramic system was prepared using the conventional solid-state method. The X-ray diffraction patterns of the B2O3-doped 0.45La0.97Sm0.03(Mg0.5Sn0.5)O3–0.55Ca0.8Sm0.4/3TiO3ceramic system did not significantly vary with sintering temperature. A dielectric constant of 35.5, a quality factor (Q×f) of 5,500 GHz, and a temperature coefficient of resonant frequency of −1 ppm/°C were obtained when the 2 wt% B2O3-doped 0.45La0.97Sm0.03(Mg0.5Sn0.5)O3–0.55Ca0.8Sm0.4/3TiO3ceramic system was sintered at 1450°C for 4 h. [ABSTRACT FROM PUBLISHER]

The La1− xYb x(Mg0.5Sn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the La0.97Yb0.03(Mg0.5Sn0.5)O3 ceramics revealed no significant variation of phase with sintering temperatures. An apparent density of 6.65 g/cm3, a dielectric constant ( εr) of 20.2, a quality factor ( Q × f) of 56,800 GHz, and a temperature coefficient of resonant frequency ( τ f) of −76.9 ppm/°C were obtained for La0.97Yb0.03(Mg0.5Sn0.5)O3 ceramics that were sintered at 1550°C for 4 h. [ABSTRACT FROM AUTHOR]

Abstract: The microwave dielectric properties of (Mg(1−x)Ni x )2SnO4 ceramics were examined with a view to their exploitation for mobile communication. The (Mg(1−x)Ni x )2SnO4 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction (XRD) patterns of the (Mg0.95Ni0.05)2SnO4 ceramics revealed no significant variation of phase with sintering temperatures. A maximum density of 4.77gcm−3 was obtained for (Mg0.95Ni0.05)2SnO4 ceramic, sintered at 1550°C for 4h. Dielectric constant (ɛ r) of 8.72, quality factor (Q × f) of 103,100GHz, and temperature coefficient of resonant frequency (τ f ) of −62.8ppm°C−1 were obtained for (Mg0.95Ni0.05)2SnO4 ceramics that were sintered at 1550°C for 4h. [Copyright &y& Elsevier]

The influence of CaSrTiO on the microstructures and microwave dielectric properties of Nd(MgZnSn)O ceramics were investigated by the conventional solid-state method. The X-ray diffraction peaks of (1 − x)Nd(MgZnSn)O- xCaSrTiO ceramic system shifted to higher angles as x increased. The dielectric constant increased from 31.8 to 47.7, the quality factor ( Q × f) decreased from 54,200 to 42,800 GHz, and the temperature coefficient of resonant frequency ( τ) increased from −43 to +41 ppm/°C as x increased from 0.5 to 0.7 when (1 − x)Nd(MgZnSn)O- xCaSrTiO ceramic system sintered at 1,600 °C for 4 h. [ABSTRACT FROM AUTHOR]

Abstract: The microwave dielectric properties of La1−x Sm x (Mg0.5Sn0.5)O3 ceramics were examined with a view to their exploitation for mobile communication. The La1−x Sm x (Mg0.5Sn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the La0.97Sm0.03(Mg0.5Sn0.5)O3 ceramics revealed no significant variation of phase with sintering temperatures. Apparent density of 6.59g/cm3, dielectric constant (ε r ) of 19.9, quality factor (Q×f) of 70,200GHz, and temperature coefficient of resonant frequency (τ f ) of −77ppm/°C were obtained for La0.97Sm0.03(Mg0.5Sn0.5)O3 ceramics that were sintered at 1500°C for 4h. The dielectric constant, and τ f of La0.97Sm0.03(Mg0.5Sn0.5)O3 ceramics were almost independent with the sintering temperature as the sintering temperature varied from 1450 to 1600°C. [Copyright &y& Elsevier]

The microwave dielectric properties of Mg1/3Nb2/3SnO4 ceramics were investigated for possible mobile communication applications. The Mg1/3Nb2/3SnO4 ceramics were prepared by conventional solid-state method with various sintering temperatures. The Mg1/3Nb2/3SnO4 ceramics contained MgNb2O6 and MgNb2SnO8. The intensity of the Mg1/3Nb2/3SnO4 ceramics increased with sintering temperature to a maximum at 1475°C. An apparent density of 5.95 g/cm3, a dielectric constant (ϵ r ) of 8.32, a quality factor (Q × f) of 84,800 GHz, and a temperature coefficient of resonant frequency (τ f ) of -11.1 ppm/OC were obtained when Mg1/3Nb2/3SnO4 was sintered at 1450°C for 4h. [ABSTRACT FROM PUBLISHER]

Abstract: The microwave dielectric properties of La(Mg0.5−x Ca x Sn0.5)O3 ceramics were examined with a view to their exploitation for wireless communications. The La(Mg0.5−x Ca x Sn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The La(Mg0.5−x Ca x Sn0.5)O3 ceramics contained Ca2SnO4, CaSnO3, and La2O3. The amount of Ca2SnO4 increased with increasing sintering temperature. However, the relative amount of CaSnO3 decreased with increasing sintering temperature. An apparent density of 6.52g/cm3, a dielectric constant (ε r ) of 20.2, a quality factor (Q×f) of 80,500GHz, and a temperature coefficient of resonant frequency (τ f ) of −79ppm/°C were obtained for La(Mg0.4Ca0.1Sn0.5)O3 ceramics that were sintered at 1500°C for 4h. [Copyright &y& Elsevier]

The microwave dielectric properties of La2.9/3Ba0.05(Mg0.5Sn0.5)O3 ceramics were prepared with a view to their potential for mobile communication. The La2.9/3Ba0.05(Mg0.5Sn0.5)O3 ceramics were prepared by the conventional solid-state method. B2O3 was selected as a liquid sintering aid to reduce the sintering temperature of La2.9/3Ba0.05(Mg0.5Sn0.5)O3 ceramics. The X-ray diffraction patterns of the La2.9/3Ba0.05(Mg0.5Sn0.5)O3 ceramics with 0.25 wt% B2O3 additive exhibited no significant variation of phase with sintering temperature. A maximum dielectric constant and quality factor (Q × f) were obtained for La2.9/3Ba0.05(Mg0.5Sn0.5)O3 with 0.25 wt% B2O3 additive that were sintered at 1400°C for 4 h. A temperature coefficient of resonant frequency τ f (−77 ppm/ °C) was measured when La2.9/3Ba0.05(Mg0.5Sn0.5)O3 ceramics with 0.25 wt% B2O3 that were sintered at 1400°C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of La(Mg0.5-xZnxSn0.5)O3 ceramics were examined with a view to their exploitation for mobile communication. The La(Mg0.5-xZnxSn0.5)O3 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the La(Mg0.45Zn0.05Sn0.5)O3 ceramics revealed La(Mg0.45Zn0.05Sn0.5)O3 is the main crystalline phase, which is accompanied by small amounts of La2Sn2O7 as the second phases. Apparent density of 6.59 g/cm3, dielectric constant (ϵr ) of 19.82 and quality factor (Q × f) of 41,600 GHz were obtained for La(Mg0.49Zn0.01Sn0.5)O3 ceramics that were sintered at 1550°C for 4 h. [ABSTRACT FROM AUTHOR]

Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics prepared by the conventional solid-state method have been investigated for application in monopole antenna loaded with high permittivity superstrate. CuO was selected as a liquid sintering aid to reduce the sintering temperature of Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics. The X-ray diffraction patterns of the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics exhibited no significant phase difference with 0.10 and 0.25 wt% CuO additive at different sintering temperatures. A permittivity of 19.5 and a quality factor (Q × f) of 18,600 GHz can be obtained when the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.10 wt% CuO additive that were sintered at 1450°C for 4 h. The temperature coefficient of resonant frequency τ f (−59.0 ppm/°C) was measured for Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.10 wt% CuO additive sintered at 1450°C for 4 h. The measurement result of monopole antenna loaded with high permittivity superstrate at 2.42 GHz was presented. A 18.60% bandwidth (return loss < 10 dB) with a center frequency at approximately 2.42 GHz was successfully achieved. [ABSTRACT FROM AUTHOR]

In this study, the microwave dielectric properties of La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics prepared by the conventional solid-state method had been investigated for application in mobile communication. B2O3 was selected as a liquid sintering aid to reduce the sintering temperature of La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics. It was found that with 0.25 wt% B2O3 additive, the X-ray diffraction patterns of the La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics exhibited no significant phase difference at different sintering temperatures from 1350 to 1500°C. The maximum values of the dielectric constant and the quality factor (Q × f) could be obtained when the La2.98/3Sr0.01(Mg0.5Sn0.5)O3 with 0.25 wt% B2O3 additive were sintered at 1450°C for 4h. The temperature coefficient of resonant frequency τf (-77.0 ppm/°C) was measured of La2.98/3Sr0.01(Mg0.5Sn0.5)O3 ceramics with 0.25 wt% B2O3 sintered at 1450°C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of V2O5-doped (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 ceramic system prepared by the conventional solid-state method were investigated with a view to their potential for mobile communication. The X-ray diffraction peaks of (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 shifted to higher angles as x increased from 0.4 to 0.7. The X-ray diffraction patterns of the 0.4La(Mg0.5Sn0.5)O3-0.6CaTiO3 revealed no significant variation of phase with sintering temperatures. The average grain size of the 0.4La(Mg0.5Sn0.5)O3-0.6CaTiO3 increased from 3.1 to 8.6 μm as the sintering temperature increased from 1400 to 1550°C. The dielectric constant increased from 28.5 to 48.7 and the quality factor (Q × f) decreased from 46,800 to 22,900 GHz for (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 as x increased from 0.4 to 0.7 that were sintered at 1550°C for 4h. The average value of temperature coefficient of resonant frequency (τf) increased from -56 to +46 ppm/°C as x increased from 0.4 to 0.7. [ABSTRACT FROM AUTHOR]

Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics prepared by the conventional solid-state method have been investigated for application in inverted-L monopole antenna. B2O3 was selected as a liquid sintering aid to lower the sintering temperature of Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics. It was found that the X-ray diffraction patterns of the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics exhibited no significant phase difference with 0.25 and 0.5 wt% B2O3 additive at different sintering temperatures. The maximum values of the dielectric constant and the quality factor (Q × f) can be obtained when the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.25 wt% B2O3 additive were sintered at 1400°C for 4 h. The temperature coefficient of resonant frequency [image omitted] (-65.2 ppm/°C) was measured for Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.25 wt% B2O3 additive sintered at 1400°C for 4 h. The measurement result of inverted-L monopole antenna at 3.5 GHz was presented. With this technique, a 32.39% bandwidth (return loss < 10 dB) with a center frequency at approximately 3.55 GHz was successfully achieved. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of CaLa(4-x)NdxTi5O17 ceramics were studied with a view to their potential for rectenna. The diffraction peaks of CaLa(4-x)NdxTi5O17 ceramics nearly unchanged as x increased from 0 to 0.007. The X-ray diffraction peaks of the CaLa3.995Nd0.005Ti5O17 ceramics revealed no significant variation of phase with sintering temperature. A dielectric constant of 57.2, a quality factor (Q × f) of 15700 GHz, and a temperature coefficient of resonant frequency (τf) of -14 ppm/°C were obtained for CaLa3.995Nd0.005Ti5O17 ceramic sintered at 1500°C for 4 h. [ABSTRACT FROM AUTHOR]

The microwave dielectric properties of B2O3-doped (1 - x)La(Mg0.5Sn0.5)O3-xCa0.8Sr0.2TiO3 ceramics were investigated with a view to their potential for mobile communication devices. The B2O3-doped (1 - x)La(Mg0.5Sn0.5)O3-xCa0.8Sr0.2TiO3 ceramics were prepared by the conventional solid-state method. A dielectric constant of 39.5, a quality factor (Q × f) of 23,200 GHz, and a temperature coefficient of resonant frequency (τf) of 0 ppm/°C were obtained for 1.0 wt% B2O3-doped 0.4La(Mg0.5Sn0.5)O3-0.6Ca0.8Sr0.2TiO3 ceramics that were sintered at 1400°C for 4 h. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the microwave dielectric properties of La2.98/3Ba0.01(Mg0.5Sn0.5)O3 ceramics prepared by the conventional solid-state method have been investigated for application in mobile communication. B2O3 was selected as a liquid sintering aid to lower the sintering temperature of La2.98/3Ba0.01(Mg0.5Sn0.5)O3 ceramics. It was found that with 0.25wt% B2O3 additive, the X-ray diffraction patterns of the La2.98/3Ba0.01(Mg0.5Sn0.5)O3 ceramics exhibited no significant phase difference of different sintering temperatures from 1350 to 1550°C. The maximum values of the dielectric constant and the quality factor (Q × f) can be obtained when the La2.98/3Ba0.01(Mg0.5Sn0.5)O3 with 0.25wt% B2O3 additive were sintered at 1400°C for 4h. The temperature coefficient of resonant frequency τ f (−72ppm/°C) was measured of La2.98/3Ba0.01(Mg0.5Sn0.5)O3 ceramics with 0.25wt% B2O3 sintered at 1400°C for 4h. [Copyright &y& Elsevier]

In this study, the microwave dielectric properties of (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 ceramic system prepared by the conventional solid-state method have been investigated for application in mobile communication. It was found that the diffraction peaks of (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 ceramic system shift to higher angles as x increases from 0.4 to 0.7. It was also found that the X-ray diffraction patterns of the 0.4La(Mg0.5Sn0.5)O3-0.6CaTiO3 ceramics exhibited no significant phase difference at different sintering temperatures. The average grain size of the 0.4La(Mg0.5Sn0.5)O3-0.6CaTiO3 ceramics increases from 2.0 to 4.1 μm as the sintering temperature increased from 1250 to 1400°C. The dielectric constant increased from 27.7 to 49.4 and the quality factor (Q × f) decreased from 12,600 to 3,200 GHz for (1-x)La(Mg0.5Sn0.5)O3-xCaTiO3 ceramic system as the x value increases from 0.4 to 0.7 sintered at 1400°C for 4h. The average value of temperature coefficient of resonant frequency ([image omitted]) increased from -65 to +46 ppm/°C as the x value increases from 0.4 to 0.7. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the microwave dielectric properties of La(Mg0.5Sn0.5)O3 ceramics have been investigated for application in mobile communication. B2O3 was selected as a liquid sintering aid to lower the sintering temperature of La(Mg0.5Sn0.5)O3 ceramics. It was found that the X-ray diffraction patterns of the La(Mg0.5Sn0.5)O3 ceramics exhibited no significant phase difference with 0.5wt% at different sintering temperatures. The maximum values of the dielectric constant and the quality factor multiples resonant frequency (Q × f) can be obtained when the La(Mg0.5Sn0.5)O3 with 0.5wt% B2O3 additive were sintered at 1500°C for 4h. The temperature coefficient of resonant frequency τ f (−85ppm/°C) was measured for La(Mg0.5Sn0.5)O3 ceramics with 0.5wt% B2O3 sintered at 1500°C for 4h. [Copyright &y& Elsevier]

Abstract: In this paper, the microwave dielectric properties of 0.95MgTiO3–0.05CaTiO3 ceramics have been studied for application in dielectric resonator antenna design. ZnO was selected as liquid sintering aids to lower the sintering temperature of 0.95MgTiO3–0.05CaTiO3. The X-ray diffraction pattern exhibited single phase for ceramics up to 1.0wt.%. The maximum dielectric constant was obtained for samples after 0.25wt.% ZnO addition and 1290°C for 4h sintering. A near-zero temperature coefficient of resonant frequency (τ f) of −4.9ppm/°C was obtained for 0.95MgTiO3–0.05CaTiO3 ceramics with 0.25wt.% ZnO sintered at 1250°C for 4h. The dielectric resonator antenna measured at 9.58GHz exhibited a 5.92% bandwidth (return loss <−10dB) of center frequency. [Copyright &y& Elsevier]

Abstract: Effect of DC biasing field on the real part of the relative dielectric constant of (Ba0.6Sr0.4)TiO3 and ZrO2-doped (Ba0.6Sr0.4)TiO3 for application in phased array antennas have been characterized. The composites have adjustable dielectric properties. The grain size is maximum for (Ba0.6Sr0.4)TiO3 doped with 0.5 wt.% ZrO2 content. The real part of the relative dielectric constant of the specimens decreases with increasing applied DC biasing field. The tunability and grain size have similar trends as a function of ZrO2 contents. The tunability of the real part of the relative dielectric constant for (Ba0.6Sr0.4)TiO3 doped with 0.5 wt.% ZrO2 content is about 45.74% and 45.88% at 20 and 40 MHz, respectively. [Copyright &y& Elsevier]

The microwave dielectric properties of (Mg(1?x) Cox)2SnO4 ceramics were examined with a view to their exploitation for mobile communication. The (Mg(1?x)Cox)2SnO4 ceramics were prepared by the conventional solid-state method with various sintering temperatures. The X-ray diffraction patterns of the (Mg(1?x)Cox)2SnO4 ceramics revealed no significant variation of phase with sintering temperatures. Specimens were not single-phase materials; small amounts of MgO and SnO2 as the second phases were observed in all specimens. A dielectric constant (?r) of 8.8, a quality factor (Q ? f ) of 110 800 GHz (at 16.4 GHz), and a temperature coefficient of resonant frequency (?f) of ?66 ppm/°C were obtained for (Mg0.93Co0.07)2SnO4 ceramics that were sintered at 1550°C for 4 h. The proposed dual-band co-planar waveguide (CPW)-fed inverted-E-shaped monopole covered the industrial, scientific, medical (ISM), high-performance radio local area network (HIPERLAN), and unlicensed national information infrastructure (UNII) bands. A 13.62% bandwidth (return loss <10 dB) of 2.43 GHz, and a 20.69% bandwidth (return loss <10 dB) of 5.38 GHz was successfully achieved. [ABSTRACT FROM PUBLISHER]