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An ultra-miniaturized meander line inspired dual-band filters with and without open stub loaded rectangular resonator defected on the ground plane are presented. The dual-band characteristic is obtained from half wavelength rectangular resonator which eliminating certain frequency bands forming dual-band operation. The transmission zero in the pass band is determined by modifying the dimensions of the resonator. The miniaturized meander line DGS-based filter is analyzed with and without rectangular resonator. The rectangular resonator incorporated with meander line coupling acts a crucial part in dual-band filters (DBFs). The miniaturization of DGS-based meander line inspired filters can be realised by varying the overall substrate size for (20 × 20) mm, (10 × 10) mm and (5 × 5) mm. The proposed DBF with rectangular resonator produces tremendous bandwidth ranges from 1.2 to 6.8 GHz (Band I) and 7.2–12.4 GHz (Band II) whose bandwidths are 5.6 GHz and 5.2 GHz, respectively. The filter characteristics show the filter’s return loss (S11) of − 29.55 dB and insertion loss (S21) of − 2.45 dB. The proposed DBF without rectangular resonator produces tremendous bandwidth ranges from 1.2 to 8.2 GHz (Band III) and 9–13.8 GHz (Band IV) whose bandwidths are 7 GHz and 4.8 GHz, respectively. The filter characteristics show the filter’s return loss (S11) of − 32.2 dB and insertion loss (S21) of − 1.35 dB. The performances of both filters are evaluated and analysed through S-parameters. Also, the measured results of both the filters obey the simulated results. The proposed filter is confined with the size of (10 × 10 × 1.6) mm3 or (0.15) $$\lambda_{g}^{2}$$ which is nearly 200% less when compared with other existing design.

Slotted ground microstrip antenna can be devised to radiate electromagnetic waves in the allotted bands for location tracking (LT) applications. The signal is fed through a microstrip feed line towards the centre of the substrate. The rectangular slots placed in the ground plane are carefully designed to propagate linearly polarized signals in two bands viz. 4.66 - 4.77 GHz (the band I) and 6.13 - 6.67 GHz (the band II). The antenna produces a fair gain in both the bands.

This paper presents the design consideration on a converged Rx surface acoustic wave (SAW) duplexer module for integrated RF front end. Two different matching-circuit and notch-circuit configurations were examined with importance placed on electrical characteristics (insertion loss and isolation of duplexer) and simplification of module, respectively. From circuit simulations and examinations, we verified that a simplified design was best in terms of both characteristics and space in the case of a finite inductor’s Q. We also fabricate a quad-band converged Rx module (Band I + II, V + VIII) using an SAW duplexer and verified that its electrical characteristics agree well with our simulation results.

The High Dynamic Front End Receiver for Band-I (30–80 MHz) for uGMRT developed by Front End Group at GMRT. Four dipoles are used in quad configuration, one pair of dipoles for vertical and another pair of dipoles for horizontal is connected to a power-combiner. The band pass filter is used to suppress out of band rejection and pass 30–80 MHz signal. The polarizer is used before the LNA which converts the received linear polarization to circular. To calibrate the gain of the receiver chain, there is provision to inject an additional noise signal (ENR of 30 dB) into the input of the LNA using directional coupler. It is possible to inject noise at any one of four levels. These are called Low cal, Medium cal, High cal and Extra high cal. To minimize crosstalk between two channels (CH-1 and CH-2) signals a phase switching facility using separate Walsh functions for each signal path is provided at the RF section of the receiver. Additional low pass and band stop filter is used after High Dynamic post amplifier for further suppression of SW and FM band. The RF power detector is used for RF CH power monitoring.

International audience; In this paper, the development of a new device for high temperature emissivity measurement is described. This device aims at measuring both spectral and total emissivity for a thermal range of 600–1000 °C. The main targeted properties of this device are versatility and simplicity. To achieve this, a rigorous selection of components such as heating systems, heat sources, sample holders, and measuring devices was made. Sample dimensions and the corresponding sample holder were optimized through a ray tracing model computation. Selection of sensors to compute the total emissivity was also discussed. A near-infrared (NIR) spectrometer and two mid-infrared (MIR) cameras equipped with optical filters covering the bandwidth of 3–5 and 7.5–13 μm were chosen for spectral measurements. The major impediment was the separation of the sample signal and various spurious signals emitted by the environment. A specific measurement methodology was then made for each bandwidth to resolve this issue. Platinum was chosen as the reference material for the device validation. Spectral emissivity measurements were then compared to values from a commercial spectrometer. A good agreement was found between NIR and MIR band I measurements, and a higher error rate was seen in MIR band II which is explained by a less favorable signal to noise ratio. Integrated emissivity is then calculated and compared to values found in the literature. A good agreement between these values is found, and similar trends with temperature are observed. The device is then validated for spectral and total emissivity measurements. Device versatility and simplicity allow for an easy adaptation to a large area of applications.

This paper presents a novel mixed-signal low-power dual-band square/triangular waveform generator (WFG) chip with a wide low-frequency tuning range for medical bio-electric stimulation therapy. It consists of a relaxation oscillator comprising a hysteresis Schmitt trigger and a timing integrator, along with frequency divider (FD) stages and path selector output for driving an electrode from 16 selectable channels. It was fabricated using Global Foundries 8RF-DM 130-nm CMOS process with a supply voltage of ±1 V for the oscillator and +1 V for logic circuits. The WFG provides an output of around 1.5 $\text{V}_{\textrm {p-p}}$ at a nominal low oscillation frequency of 17 kHz using small-size on-chip passive components of values 10 $\text{k}\Omega $ and 10 pF. The WFG core (band I) can be tuned in the range 6.44–1003 kHz through bias current adjustment, while a lower frequency (band II) in the range 0.1 Hz–502 kHz can be provided digitally through a $\div 2$ stage. The power consumption was only 0.457 mW for the WFG and 2.1 mW for the FD circuit while occupying a total silicon area of only 18 $426~\mu \text{m}^{2}$ .

The proliferation of man-portable air-defense systems (MANPADS) is extremely wide. MANPADS are responsible for over 60% of total aircraft casualties since 1960’s. It is estimated that over 500,000 of these systems are deployed worldwide with a large number being out of governmental control. Directional infrared countermeasure (DIRCM) systems have been deployed in order to counter the threat. Laser based DIRCM system requires laser sources which can operate in bands I, II and IV. Up to day bands II and IV are covered by compact and lightweight quantum cascade lasers (QCLs), but for wavelength generation in band I, bulky and expensive solid-state or fiber laser solutions are used. Recent development of GaSb laser diode technology at Brolis Semiconductors greatly improved optical output powers and efficiency of laser diodes working in 1900 - 2450 nm range (band I). In this work we present a laser diode module which is based on incoherent beam combining of two high-power GaSb laser diode emitters working in 2.1-2.3 μm spectral band. This laser module is capable of providing directional beam with radiant intensity value of more than 30 kW/str. Module is extremely compact and lightweight (

A highly linear fully integrated RF power amplifier (PA) for advanced long-term evolution (LTE-advanced) is fabricated in a 180-nm standard silicon-on-insulator process. To improve the linearity, several harmonic traps are introduced to minimize the second- and third-order harmonics, and hence, the third-order intermodulation distortion (IMD3). The impact on the linearity of the RF PA of each of the harmonic controls is studied and simulated. Finally, both the linearity of a standalone RF PA and an RF PA with proposed linearity enhancement circuitry is investigated by comparing their measured IMD3. For an LTE uplink signal with 20-MHz signal bandwidth and a 64-QAM 8.7-dB peak-to-average power ratio, the RF PA achieves 21.7% power-added efficiency (PAE) with 11-dB gain while delivering an average output power of 22.4 dBm in LTE-band VII. Simultaneously, the RF PA obeys the stringent spectral mask and the $-$ 30-dBc adjacent channel leakage ratio linearity requirement and achieves an error vector magnitude of only 4.05%. The linearized wideband RF PA is also verified for LTE-band I and achieves similar performance from 1.9 to 2.8 GHz. Thanks to the applied linearization technique, the proposed RF PA is able to transmit an LTE-advanced (release 12) signal with a carrier-aggregated bandwidth up to 60 MHz while satisfying the linearity requirements. For a 40-MHz (2 $\times$ 20 MHz) and 60-MHz (3 $\times$ 20 MHz) LTE-advanced signal at band VII, the RF PA produces an average output power of 19.2 and 17.6 dBm while achieving a PAE of 17.2% and 13.7%, respectively.

A two dimensional (2D) finite element model of thin film bulk acoustic wave resonator (FBAR) is created in COMSOL Multiphysics to investigate the shifting of the parallel and series resonance frequencies as a function of the thickness of the electrodes. The dependence of the electromechanical coupling coefficient and quality factor from electrode thickness is also studied. A classical FBAR with aluminum nitride as piezoelectric layer and aluminum electrodes is modeled. The piezoelectric layer is chosen to resonate in the Personal Communications Service Band I (Tx: 1850.2–1909.8 MHz; Rx: 1930.2–1989.8 MHz). A methodology to build a 2D model of a FBAR in COMSOL and parameterize the electrode thickness is described.

We report the first measurements of radio frequency spectrum occupancy performed at sites aimed to host the future radio astronomy observatory in Indonesia. The survey is intended to obtain the radio frequency interference (RFI) environment in a spectral range from low frequency 10 MHz up to 8 GHz. The measurements permit the identification of the spectral occupancy over those selected sites in reference to the allocated radio spectrum in Indonesia. The sites are in close proximity to Australia, the future host of Square Kilometre Array (SKA) at low frequency. Therefore, the survey was deliberately made to approximately adhere the SKA protocol for RFI measurements, but with lower sensitivity. The RFI environment at Bosscha Observatory in Lembang was also measured for comparison. Within the sensitivity limit of the measurement equipment, it is found that a location called Fatumonas in the surrounding of Mount Timau in West Timor has very low level of RFI, with a total spectrum occupancy in this measured frequency range being about 1 %, mostly found at low frequency below 20 MHz. More detailed measurements as well as a strategy for a radio quiet zone must be implemented in the near future.

We report the first measurements of radio frequency spectrum occupancy performed at sites aimed to host the future radio astronomy observatory in Indonesia. The survey is intended to obtain the radio frequency interference (RFI) environment in a spectral range from low frequency 10 MHz up to 8 GHz. The measurements permit the identification of the spectral occupancy over those selected sites in reference to the allocated radio spectrum in Indonesia. The sites are in close proximity to Australia, the future host of Square Kilometre Array (SKA) at low frequency. Therefore, the survey was deliberately made to approximately adhere the SKA protocol for RFI measurements, but with lower sensitivity. The RFI environment at Bosscha Observatory in Lembang was also measured for comparison. Within the sensitivity limit of the measurement equipment, it is found that a location called Fatumonas in the surrounding of Mount Timau in West Timor has very low level of RFI, with a total spectrum occupancy in this measured frequency range being about 1 %, mostly found at low frequency below 20 MHz. More detailed measurements as well as a strategy for a radio quiet zone must be implemented in the near future.

The spectral line parameters of carbon dioxide have been measured in the laser band I (00011 ← 10001) centred at 10.4 μm. The spectra were recorded at room temperature using the spectroscopic instrumentation at the far-infrared beamline, Canadian Light Source, Saskatoon, Sask. The spectral line intensities, air- and self- broadened Lorentz half widths, and pressure-induced shift coefficients were retrieved for 48 spectral lines using a multispectrum fit technique (Benner et al. J. Quant. Spectrosc. Radiat. Transfer, 53, 705 (1995)). Line parameters were retrieved using the Voigt and speed-dependent Voigt models. The deviations between our results and other results reported in the literature and in the HITRAN08 (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)) database were examined and discussed. The effect of errors in fitting channel spectra parameters was examined and found to be mitigated by the inclusion of channels in the multispectral fit.

In this article, a simple printed monopole slot antenna with two parasitic shorted strips (a longer parasitic shorted strip and a shorter parasitic shorted strip) for penta-band wireless wide area network operation in the slim mobile phone is presented. The monopole slot has a length of 40 mm only and is disposed near the bottom edge of the system ground plane of the mobile phone with a small distance of 6.5 mm. By adding longer parasitic shorted strip connected to the bottom corner edge of the system ground plane, good excitation of the monopole slot antenna at its fundamental (quarter-wavelength) mode and chassis dipole-type mode of the system ground plane can be obtained. The shorter parasitic shorted strip contributes additional resonant mode to the antenna. The excited resonant modes form two wide operating bands to cover the GSM850/900 operation (824–960 MHz) and GSM1800/1900/WCDMA Band I operation (1710–2170 MHz), respectively. Details of the proposed antenna are presented. The specific absorption rate results for the antenna with the presence of the head and hand phantoms are also studied. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2835–2841, 2013

In this work, we investigated the temperature-dependent luminescence of bovine serum albumin-protected Au25 nanoclusters and the correlation with their structure. Our experiments reveal that the red luminescence consists of two bands, namely, band I at 710 nm and band II at 640 nm. The temperature dependence of band I exhibits similarity to semiconductors, such as a red shift of emission and bandwidth broadening upon increasing temperatures due to electron–phonon and electron–defect/surface scattering. In contrast, band II exhibits different temperature dependence. It is concluded that band I exclusively originates from the icosahedral core of 13 Au(0) atoms and band II dominantly arises from the [−S–Au(I)–S–Au(I)–S−] staples. Moreover, with increasing temperatures, the intensity of band I and band II decreases. A similar activation energy was extracted, which is attributed to thermally activated defect/surface trapping. In addition, the relaxation from band II to band I was found to be inactive from 300 ...

In this paper, a compact near fleld reader antenna is proposed for ultra-high frequency (UHF) radio frequency identiflcation (RFID) applications. The antenna structure is composed of two split-ring-resonators (SRRs) and miniaturized to a special small size of 21 ⁄ 21 ⁄ 1:6mm 3 for mobile RFID application. The measured bandwidth of antenna prototype is 13MHz (914.5{927.5MHz) with re∞ection coe-cient less than i10dB, which covers the China RFID band II (920{925MHz). Simulation shows that the proposed antenna achieves a strong and uniform magnetic fleld distribution in the near fleld region, and the reading range is up to 42mm with near fleld RFID tag. Through modifying the parameters of SRRs, the antenna can operate on difierent UHF RFID bands (Europe band, China band I&II etc.).

This paper aims at optimizing utilization of Frequency Modulation (FM) band following Uganda Communications Commission (UCC)'s halt on licensing of new FM radios. Using the energy detection technique, Chowning's FM model and Carson's rule; the paper reveals that UCC's region 9, with 64 licensed FM radio stations, has 9.4% channel occupancy but 102 stations can be licensed. Consequently; more 1128 FM radio stations can be licensed, countrywide, improving the utilization from 33.5% to 99.5%.

A SiO(2)/Al/LiNbO(3) structure has a large electromechanical coupling factor (K(2)) and good temperature coefficient of frequency (TCF) for applications as a SAW duplexer of the Universal Mobile Telecommunications System (UMTS) Band I. However, the SiO(2)/Al/LiNbO(3) structure also supports two unwanted spurious responses; one is caused by the Rayleigh mode and the other by the transverse mode. As the authors have previously discussed, the Rayleigh-mode spurious response can be suppressed by controlling the cross-sectional shape of a SiO(2) overlay deposited on resonator electrodes. In this paper, a new technique to suppress the transverse-mode spurious responses is proposed. In the technique, the SiO(2) overlay is selectively removed from the dummy electrode region. The spurious responses are analyzed by the laser probe system. The results indicate that the spurious responses in question were hybrid modes caused by the coupling between the main (SH) SAW and another (Rayleigh) SAW with different velocities. The hybrid-mode spurious behavior was dependent on the velocities in the IDT and the dummy regions (v(i) and v(d)). The hybrid-mode spurious responses could be suppressed by selectively removing SiO(2). Furthermore, the SAW energy confinement could be enhanced in the IDT electrode region when v(i)v(d). The transverse-mode spurious responses were successfully suppressed without degrading the SAW resonator performances.

In this paper, we describe the development of a miniature surface acoustic wave (SAW) duplexer for Band I in the standard of the Third-Generation Partnership Project (3GPP) at a 2 GHz band. We employed a shear-horizontal SAW on a SiO2 overlay/thick Al electrode/5°YX-LiNbO3 structure, which offers a high electromechanical coupling coefficient (K2) as well as a small temperature coefficient of frequency (TCF). This feature is crucial for the realization of a wide duplex gap between the transmitting and receiving bands in the Band I specification. We investigated experimentally that the spurious response caused by the Rayleigh-mode could effectively be suppressed by controlling the cross-sectional shape of a SiO2 overlay on interdigital transducer (IDT) electrodes. In addition, the result also showed how this spurious response depends on IDT design parameters, i.e., electrode pitch and metallization ratio. The developed SAW duplexer was installed in a 2.5×2.0 mm2 package, and exhibited a low insertion loss, a high out-of-band rejection and a small TCF.

The digital sound broadcasting DRM (Digital Radio Mondiale) standard has established worldwide, and the number of transmissions on air has increased significantly since the approval of the standard. This paper presents the results of the one of the first DRM field trials using the 26 MHz band for local broadcasting that were carried out in Mexico. The main objective of these trials was to test the usage of the 26 MHz frequency broadcasting band to cover a local area in a similar way to FM broadcasting. This band has been usually used to broadcast long distance transmissions mainly under high sun-spot activity. When the 26 MHz band is used for local broadcasting, the tropospheric propagation is the main mechanism instead of the ionospheric refraction used in HF. At these frequencies the first Fresnel ellipsoid is usually obstructed, and multipath at urban environments is strong. In this article, practical minimum signal-to-noise ratio and field strength levels are calculated for this novel usage of the 26 MHz frequency band

A new LC-tank VCO to minimize frequency drift due to temperature variations for cellular applications is presented. By employing the feed-forward VCO gain multiplication technique, frequency drift is reduced by 83% without resorting to conventional temperature dependent biases and circuits. Additionally, the compensation circuit retains the original VCO behavior with no degradation in performance. A fractional-N PLL fabricated in 40 nm CMOS shows that the VCO draws 9 mA and the temperature compensation circuit draws 200 µA. Measurements show that the VCO has a tuning range of 46% (from 2890 MHz to 4560 MHz) and a phase noise of −102 dBc/Hz at 200 kHz offset centered at 3960 MHz at the PLL output before the divide-by-two circuit for 3G/LTE Band I.

Longlines are used for blue mussel farming in Norway. Rigs using combined spat collectors and growth bands are preferred, because they make the production more cost effective. An experiment with four different types of combined collectors (Alesund band I and II, Fiskevegn stocking, Swedish band) was conducted on two production sites to investigate, which factors affected the attachment of spats. Alesund band I and II are 5 cm wide flat bands made of a combination of polypropylene (PP) and polyester (PES) fibres. In Alesund band I the PP threads are grouped in seven vertical lines, whereas in Alesund band II the PP threads are spread uniformly over the width of the band. The Fiskevegn stocking is a loose crochet rope made of a combination of PP and PE (polyethylene) fibres. The Swedish band is a 5 cm wide white PP band. The results showed that the amount of mussels that can be harvested was highly dependent on the type of collector. On both sites the amount of harvested mussels was largest for the Swedish band, which averaged between 25 and 30 kg mussels per collector of length 6.1 m. The average amount of harvested mussels on the three other collectors was between 14 and 18 kg. Both shape and surface structure of the collector seems to be important. A dense structure, such as in the Swedish band, provided several attachment points for the byssal threads. The attachment between the mussels and the collector surface was also stronger. In the experiment, the mussels showed no preferences for collectors with thready and filamentous surfaces (Fiskevegn stocking). A collector band must be stiff enough to prevent folding of the band as the weight of the mussels increases. Folding occurred on both Alesund band I and II, but not on the Swedish band. Suboptimal structure and surface quality of the collectors may result in large initial attachment of spats followed by a large spatfall later in the growth period. In the experiments, the number of spats was over 4500/m after the first growing season. At harvesting, the mussel densities had been reduced to 600–800 mussels per m collector.

Last mile residential connectivity and the demand for increased indoor coverage and capacity in 3G cellular systems has led to the commercial introduction of femtocell (Home Node B) base stations. To achieve higher component integration, support additional functionality, and decrease power, there is a need to minimize component count, PCB area and power consumption without sacrificing performance, while also preserving backwards-compatibility with legacy 2G systems. In this paper, we present a 65nm CMOS 3G/HSPA+ femtocell transceiver with 350mW power consumption that eliminates the need for Tx SAW filters. The proposed solution supports 10 TX (Downlink) and 10+10 (Downlink+Uplink) RX UMTS bands from Band I to Band VI and Band VIII to Band XI, quad-band GSM sniffing and GPS band receive capability for soft GPS operation.

An LTE-enabled smartphone is a software-defined radio system that must cover a large number of frequency bands with different duplex differences. A proposed adaptive wideband duplexer needs a circulator to create the required initial isolation. To replace this an LC-based tunable low-isolation device is presented in this paper, providing the required tuning range for LTE Band I, II, III and VII. The circuit is implemented in a 130nm Silicon-on-Insulator (SOI) process and provides an isolation exceeding 30dB at both transmit and receive frequencies of each specified LTE frequency band. The insertion loss from PA output to antenna port is below 2dB in LTE band I. The fabricated circuit occupies an area of 2.0mm×1.2mm.

A comparative study of the commonly used methods for the prediction of the coverage area due to a transmitter operating in the HF band is presented. Those statistical model based tools are: ITU Rec. 533, Ionospheric Communication Analysis and Prediction Program; IONCAP, Voice of America's VOACAP and Ionospheric Communication Enhanced Profile Analysis and Circuit Prediction Program; ICEPAC. The received signal due to a typical transmitter located at Cricklade, England, operating around 7.9-19.1 MHz (HF band I) is computed as a function of frequency, time and the sunspot number. The ray tracing method calculates the virtual height, the calculated results are compared with the experimental data and the discrepancies are examined.

In this paper we report the pressure broadening and the pressure-induced line shift coefficients for 46 individual rovibrational lines in both the (12)C(16)O2, 00(sup 0)1-(10(sup 0)0-02(sup 0)0)I, and 00(sup 0)1-(10(sup 0)0-02(sup 0)0)II, laser bands (laser band I centered at 960.959/cm and laser band II centered at 1063.735/cm) determined from spectra recorded with the McMath-Pierce Fourier transform spectrometer. The results were obtained from analysis of 10 long-path laboratory absorption spectra recorded at room temperature using a multispectrum nonlinear least-squares technique. Pressure effects caused by both air and nitrogen have been investigated. The air-broadening coefficients determined in this study agree well with the values in the 1996 HITRAN database; ratios and standard deviations of the ratios of the present air-broadening measurements to the 1996 HITRAN values for the two laser bands are: 1.005(15) for laser band I and 1.005(14) for laser band II. Broadening by nitrogen is 3 to 4% larger than that of air. The pressure-induced line shift coefficients are found to be transition dependent and different for the P- and R-branch lines with same J" value. No noticeable differences in the shift coefficients caused by air and nitrogen were found. The results obtained are compared with available values previously reported in the literature.

This paper presents the results of a compact wire-bond SP9T antenna switch that was designed as technology demonstrator for a 2.5 V CMOS, 250 fs Ron-Coff thin-film SOI process. Through “layout-driven” circuit design, a small die size of 1.52 mm2 was achieved for a fully integrated switch die containing RF-section, I/O pads, ESD, decoder, level shifters and dual frequency charge pump to generate negative vss. The dual frequency charge pump was a requirement to achieve a fast start-up time of 10 μs and switch rise times of 3 μs. A low insertion loss of 0.42 dB for cellular low-band at 915 MHz and 0.55 dB for cellular high-band at 1910 MHz, harmonic powers better -76 dBc over battery and Band I/V IMD3 of -110 dBm were achieved. All ports show a high ESD tolerance of 2 kV HBM.

In this paper, the frequency allocation reserved for radio astronomy in the L band set by the International Telecommunication Union (ITU), which is between 1400 and 1427 MHz, is reviewed. We argue that the nearby frequencies are still very important for radio astronomers on the ground by investigating radio objects (H i sources) around 1300–1500 MHz. The L-band window is separated into a group of four windows, namely 1400–1427 MHz (window A), 1380–1400 MHz (window B), 1350–1380 MHz (window C), and 1300–1350 MHz (window D). These windows are selected according to their redshifts from a rest frequency for hydrogen spectral line at 1420.4057 MHz. Radio objects up to z ≈ 0.1 or frequency down to 1300 MHz are examined. We argue that since window B has important radio objects within the four windows, this window should also be given to radio astronomy. They are galaxies, spiral galaxies, and galaxy clusters. This underlines the significance of window B for radio astronomers on the ground. By investigating the severeness of radio frequency interference (RFI) within these windows, we have determined that window B still has significant, consistent RFI. The main RFI sources in the four windows have also been identified. We also found that the Department of Civil Aviation of Malaysia is assigned a frequency range of 1215–1427 MHz, which is transmitted within the four windows and inside the protected frequency for radio astronomy. We also investigated the RFI in the four windows on proposed sites of future radio astronomy observatories in Malaysia and Thailand and found the two best sites as Universiti Pendidikan Sultan Idris (UPSI) and Ubon Ratchathani, respectively. It has also been determined that RFI in window B increases with population density.

The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals (olivine and pyroxene) of mare basalts, which have two obvious absorption bands at 1000 nm (Band I) and 2000 nm (Band II). Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper (M 3 ) data are widely used for lunar mineral identification. However, M 3 data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M 3 data taken during different optical periods, Optical Period 1B (OP1B) and Optical Period 2A (OP2A). Two programs for continuum removal are reported in this paper. Generally, a program respectively constructs two straight lines across Band I and Band II to remove the continuum, which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2480 and 2560 nm for OP1B and OP2A data, respectively. The band center values derived from OP1B data are smaller than those derived from OP2A data in Band I but larger in Band II, especially for the spectra using longer right endpoints (>2600 nm). This may be due to the spectral slopes of OP1B data being steeper than those of OP2A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.

Based on effects of lateral coupling between the resonant L3 cavity and tow quasi waveguides bends in tow dimensional photonic crystal (2D PhC) who depends strongly on the parameters of geometry of the PC lattice, especially on the dielectric rods sizes. We proposed Photonic Crystal BandPass Filter (PCBPF), the out put transmission spectra of our filter covered three band. Band I covers the wavelength range from 1.331 to 1.355 µm has 86% of transmission power, Band II, from 1.390 to 1.427 µm, has 98% of the transmission power and Band III from 1.46 to 1.507 µm, has 27% of the transmission power. The full width at half maximum bandwidth of these bands is 9.7, 13.1 and 16.4 nm, respectively. This Filter (PCBPF) is proposed for photonic integrated circuits (PIC), wavelength division multiplexing (WDM) systems and sensing applications. The normalized transmissions spectra of this filter are obtained them using 2D Finite Difference Time Domain Method (2D-FDTD). The Photonic Band Gap is calculated by Plane Wave Expansion method (PWE).

A new design of a single layer coplanar waveguide (CPW)-fed, circularly polarized square slot antenna with a fork shape feedline is presented. By choosing proper dimensions of the feedline and grounded patch elements, two orthogonal resonant modes with 90°phase difference for circular polarization (CP) operation can be excited. Predicted results are validated through experiments. The measured 3dB axial ratio bandwidth is 36% (2112–3056 MHz) for lower band I and 9% (5292–5837 MHz) for band II. Also total measured impedance bandwidth is 7810MHz. The peak gain of the antenna is measured as 4.35 dBi.

The lifetime of luminescence in NaCl:${\mathrm{Yb}}^{2+}$ crystals has been investigated using a streak-camera method. Two emission bands peaking at 400 and 432 nm (called bands I and II, respectively) are observed. In addition to a long lifetime of more than 0.3 ms previously observed for band II, it was observed that band I has a short lifetime of less than 3 \ensuremath{\mu}s and the lifetime decreases with increasing temperature, reaching a short lifetime of 15 ns at 290 K. A kinetic analysis of the lifetimes and intensities of the bands in terms of three rate constants was made. The temperature dependence of the nonradiative rate constant was shown to be well reproduced by multiple-phonon-decay formulas.

A SiO 2 /Al/LiNbO 3 structure has a large electromechanical coupling factor (K2) and good temperature coefficient of frequency (TCF) for the UMTS Band I application. However, the SiO 2 /Al/LiNbO 3 structure also supports two unwanted spurious responses; one is caused by the Rayleigh-mode and the other by the transverse-mode. As the authors have previously discussed, the Rayleigh-mode spurious response can be suppressed by controlling the cross-sectional shape of a SiO 2 overlay deposited on resonator electrodes. On the other hand, the transverse-mode spurious responses are commonly suppressed by IDT (Interdigital Transducer) apodization, and the length weighting for dummy electrodes selectively could scatter higher-order transverse-mode spurious responses. In this paper, the spurious responses of the SAW resonator on a SiO 2 /Al/LiNbO 3 structure are analyzed by the laser probe system. And, a new technique to suppress the transverse-mode spurious responses is proposed. In the technique, the SiO 2 overlay is selectively removed from the dummy electrode region. The transverse-mode spurious behavior was dependent on the velocities (v i and v d ) in the IDT and the dummy regions. When v i d , the higher-order transverse-mode spurious response could be suppressed. Furthermore, the SAW energy confinement could be enhanced in the IDT electrode region by selectively SiO 2 removing. The transverse-mode spurious responses were successfully suppressed without degrading the SAW resonator performances.

In this paper, a single pole single zero asymmetric notch filter using RF micro electromechanical tunable capacitors is presented. The high Q value of the tunable capacitors enables this filter to achieve 25.5dB rejection with less than 1.2dB insertion loss over a 5MHz signal bandwidth. This tunable filter is designed to suppress transmission leakage in the IMT Band I (1.92–1.98GHz) band for handset WCDMA receivers. It also can serve as a component in handset tunable duplexers.

In this paper, a new 3G/GSM/EDGE multimode/ multi-band transceiver that achieves both the elimination of TX-SAW filter and the isolator using an open-loop polar modulation transmitter is presented. Sufficient ACLR performance is accomplished by a combination of parts-to-parts calibration and temperature offset compensation. ACLR meets 3GPP target specification at VSWR=3∶1, with Rx band noise at PA output in UMTS band I of −132.3dBm/Hz thus does not degrade receiver sensitivity. This paper includes design details and experimental results.

This paper describes the SiO 2 /Al/LiNbO 3 structure for the SAW duplexer. Although this structure has large electromechanical coupling coefficient, it also supports unwanted spurious responses. They are categorized into two types of the Rayleigh-mode and transverse-mode. We have developed the novel spurious suppression techniques for these spurious; the SiO 2 shape control technique for Rayleigh-mode and the scattered dummy electrode weighting for transverse-mode. We applied the proposed techniques to the balanced-type SAW duplexer for UMTS Band I system. The developed SAW duplexer was installed into a 2.5×2.0×0.5 mm3 package, and exhibited low insertion loss and high out-of-band rejection. The insertion losses in the Tx and Rx bands are 1.3dB and 2.0dB, respectively. The rejections in the Tx and Rx bands are 54 dB and 48 dB, respectively.

The UMTS Band I and Band IV systems have a wide frequency interval between transmitting (Tx) and receiving (Rx) bands. When developing a small-sized SAW duplexer for this application, one needs a substrate with a large electromechanical coupling factor (K2) and a good temperature coefficient of frequency (TCF). Although a SiO 2 /Al/LiNbO 3 structure meets these two requirements, it also supports a certain number of unwanted spurious responses. As previously discussed by the authors, the Rayleigh-mode spurious can be suppressed by controlling the cross-sectional shape of a SiO 2 overlay deposited on resonator electrodes. Here, we analyzed the Rayleigh-mode spurious behavior of a non-flat SiO 2 /Al/LiNbO 3 structure by using FEM/SDA. In this study, we applied the extended FEM/SDA to the non-flat SiO 2 /Al/LiNbO 3 structure. The SiO 2 structure has a trapezoidal shape, which we developed for suppressing the spurious responses. The analysis indicates that the spurious level due to the Rayleigh-mode decreased with a decrease in the average width of the trapezoidal region. Furthermore, the results of simulation agree well with those obtained experimentally. We have analyzed the behavior of Rayleigh-mode spurious on the non-flat SiO 2 /Al/LiNbO 3 structure. It was shown that the spurious level changes in both the shape and mass of SiO 2 on resonator electrodes.

The hero band from the Rock Band I trailer reprises its role in this 90-second trailer and engages in a car-rooftop stand off with a new rival group in a high-energy battle of the bands.

A multi-band (bands I, II, V, VIII [option]) single-chip RFIC has been implemented in 0.18µm SiGe BiCMOS process for WCDMA/HSDPA applications. The direct-conversion receiver achieves competitive system performance: −110.5dBm sensitivity, 20dB and 12dB blocking margin for ACS case 1 and case 2, respectively, and excellent in-band blocking margins. The direct-modulation transmitter achieves more than 90dB dynamic range, and excellent EVM performance: ≪3.5%. In Band I, the RX section and TX section draw each 35mA and 65mA, respectively. Two dedicated on-chip fast-settling fractional-N synthesizers provide LOs for both RX and TX. The chip is housed in a 5×5 mm2 81-pin VFBGA package.

The 26 MHz band is the highest frequency broadcasting band covered by DRM bellow 30 MHz. Due to its low use for long-range transmissions, this band is been tested for using the DRM digital radio for local coverage. This paper shows the results for mobile reception of two field trials made in Mexico City and Brasilia.