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1.
In this letter, we present a monolithically integrated up-converting active mixer that shifts a signal in the 16 GHz range up to the V-band using a 48 GHz local oscillator (LO) signal. The circuit was realized with the 0.2 /spl mu/m InP HEMT in-house process of the Swiss Federal Institute of Technology in Zurich using coplanar-waveguide technology. Measurements of the fabricated circuit show a peak conversion gain of 1 dB at 64.5 GHz for -1.7 dBm LO power, LO suppression better than 30 dB and input third-order intercept point of -1.6 dBm. This mixer will be employed in the signal up-conversion path of a 60 GHz transceiver for indoor wireless LANs.  相似文献   

2.
This work presents a fully integrated SiGe microwave up-conversion mixer, utilizing a new circuit topology consisting of a common-base, series-connected triplet at the IF port to achieve a significant improvement in dynamic range. This circuit functions with an IF signal of 1.25 GHz, and has an input 1-dB compression point (IP/sub 1dB/) of -6.8 dBm, for an RF output at 28 GHz. The circuit operates over a frequency range from 19 to 31 GHz, with a maximum conversion gain of 1 dB. The mixer can operate over an IF range from 1 to 10 GHz, while maintaining an IF port return loss greater than 10 dB.  相似文献   

3.
Fundamental and Harmonic Operation of Millimeter-Wave Gunn Diodes   总被引:1,自引:0,他引:1  
Pulsed and CW measurements in the range 26-110 GHz were performed on gallium arsenide (GaAs) Gunn diodes having active lengths of 1.8-2.6 µm, bonded into commercially available packages. The diodes were operated in full-height waveguides in the V-(WR-15), E-(WR-12), and W-(WR- 10) bands, using coaxial-bias circuits aud a disc-post resonator to provide the required resonance at their fundamental frequency in the range from about 25-65 GHz. Frequency and power measurements were performed up to 110 GHz on the fundamental, second, and third harmonics. The main emphasis of this experimental investigation has been the study of frequency changes caused by changes made in the various parameters of the disc, post, diode, diode package, and embedding waveguide sections.  相似文献   

4.
A low voltage and wide locking range injection-locked frequency divider using a standard 0.18-/spl mu/m complementary metal oxide semiconductor (CMOS) process is presented. The wide locking range and the low-voltage operation are performed by adding an injection nMOS between the differential outputs of the divider that contains on-chip transformers which result in positive feedback loops to swing the output signals above the supply and below the ground potential. This dual-swing capability maximizes the carrier power and achieves low-voltage performance. The measurement results show that at the supply voltage of 0.75-V, the divider free-running frequency is 2.02 GHz, and at the incident power of 0 dBm the locking range is about 1.49 GHz (36.88%), from the incident frequency 3.27 to 4.64GHz.  相似文献   

5.
The Institute of Electronics, Chinese Academy of Sciences, started developing X-band multibeam klystrons (MBKs) in 2000. Three types of X-band MBKs are currently under research and development; two types operate in the fundamental mode (TM010), and the other type operates in a high-order mode (coaxial TM310). These MBKs operate over the frequency range from 8 to 10 GHz and have peak powers of 50-100 kW, average powers of 2.5-5 kW, and bandwidths of 5%. The design considerations and testing results are presented in this paper. The technological problems, including nonhomogeneity of the RF electric field and low beam transmission, are also described. Further research work on the improvement of these MBKs is discussed.  相似文献   

6.
This work presents penta-notched UWB antenna with sharp frequency edge selectivity using combination of SRR, CSRR, and DGS to reject the WiMAX (3.30–3.60 GHz), lower WLAN (5.150–5.350 GHz), upper WLAN (5.725–5.825 GHz), downlink of X-band satellite communication (7.0–7.40 GHz), and the uplink of X-band satellite communication (8.10–8.50 GHz) frequency bands. All these frequency bands lie within the UWB frequency spectrum. The proposed antenna is suitable for portable communication applications due to its compact dimensions. It sharply notches the existing frequency bands to mitigate the interference caused by nearby wireless communication systems within UWB frequency range. The sharp notching is achieved by the combination of complementary split ring resonators (CSRR) on the radiating semi-circular patch, split ring resonators (SRR) placed at the junction of the feedline, and a pair of defected ground structures (DGS). All notched bands can be well controlled and shifted and the equivalent lumped model of the notched bands are also developed for validation. The proposed antenna simulated, and measured results show better performance over the present state-of-the-art designs. The proposed penta-notched UWB antenna possesses better reflection coefficient, VSWR, stable gain, and small foot print. The proposed antenna has a nearly omnidirectional radiation pattern in the passbands.  相似文献   

7.
A widely tunable microwave photonic notch filter with adjustable bandwidth based on multi-wavelength fiber laser is proposed and demonstrated. The multi-wavelength fiber laser generates the multi-taps of the microwave photonic filter (MPF). In order to obtain notch frequency response, a Fourier-domain optical processor (FD-OP) is introduced to control the amplitude and phase of the optical carrier and phase modulation sidebands. By adjusting the polarization controller (PC), different numbers of taps are got, such as 6, 8, 10 and 12. And the wavelength spacing of the multi-wavelength laser is 0.4 nm. The bandwidth of the notch filter is changed by adjusting the number of taps and the corresponding bandwidths are 4.41 GHz, 3.30 GHz, 2.64 GHz and 2.19 GHz, respectively. With the additional phase shift introduced by FD-OP, the notch position is continuously tuned in the whole free spectral range (FSR) of 27.94 GHz. The center frequency of the notch filter can be continuously tuned from 13.97 GHz to 41.91 GHz. This work has been supported by the National Natural Science Foundation of China (No.11444001), and the Municipal Natural Science Foundation of Tianjin in China (No.14JCYBJC16500). E-mail:cynever@163.com   相似文献   

8.
This paper presents a second-order delta-sigma (ΔΣ) modulator fabricated in a 70 GHz (fT), 90 GHz (fmax) AlInAs-GaInAs heterojunction bipolar transistor (HBT) process on InP substrates. The modulator is a continuous time, fully differential circuit operated from ±5 volt supplies and dissipates 1 W. At a sample rate of 3.2 GHz and a signal bandwidth of 50 MHz (OSR=32100 MSPS Nyquist rate) the modulator demonstrates a Spur Free Dynamic Range (SFDR) of 71 dB (12-b dynamic range). The modulator achieves the ideal signal-to-noise ratio (SNR) of 55 dB for a second-order modulator at an oversampling ratio (OSR) of 32. The design of a digital decimation filter for this modulator is complete and the filter is currently in fabrication in the same technology. This work demonstrates the first ΔΣ modulator in III-V technology with ideal performance and provides the foundation for extending the use of ΔΣ modulator analog-to-digital converters (ADC's) to radio frequencies (RF)  相似文献   

9.
A new hybrid technique, which is a combination of neural network (NN) and support vector machine, is proposed for designing of different slotted dual band proximity coupled microstrip antennas. Slots on the patch are employed to produce the second resonance along with size reduction. The proposed hybrid model provides flexibility to design the dual band antennas in the frequency range from 1 to 6 GHz. This includes DCS (1.71–1.88 GHz), PCS (1.88–1.99 GHz), UMTS (1.92–2.17 GHz), LTE2300 (2.3–2.4 GHz), Bluetooth (2.4–2.485 GHz), WiMAX (3.3–3.7 GHz), and WLAN (5.15–5.35 GHz, 5.725–5.825 GHz) bands applications. Also, the comparative study of this proposed technique is done with the existing methods like knowledge based NN and support vector machine. The proposed method is found to be more accurate in terms of % error and root mean square % error and the results are in good accord with the measured values.  相似文献   

10.
由于受热力学基本定律的限制 ,Si集成电路技术的发展已经日益接近极限 ,而 Si Ge材料的引入使得占据小于 1GHz频段的 Si产品可以进一步覆盖 2~ 30 GHz的 RF和无线通信市场。根据前人的材料研究工作 ,在普通 Si器件性能模拟的基础上 ,进一步研究长沟应变 Si Ge器件的模拟 ,引入了插值所得的近似因子以修正 silvaco中隐含的 Si Ge能带模型和迁移率参数。然后依据修正后的模型对 Si Ge PMOS进行更为精确的二维模拟  相似文献   

11.
Experimental results are presented on microwave amplifiers using Molybdenum Thin Film-Field-Emission cathode devices, fabricated at Stanford Research Institute (SRT). A device having 250 tips, operating at 4.8 mA of current with gm=840 μS is inferred to have an intrinsic power gain of 7 dB at 1.1 GHz. Other results are given for frequencies up to 1.7 GHz. For the first time, device and circuit modeling of sufficient accuracy has been performed that it is possible to confidently deduce the intrinsic performance parameters of the FE devices. The importance of integrated matching circuits for optimum power gain performance is exposed and quantified  相似文献   

12.
This paper presents a 5.7–6.0 GHz Phase-Locked Loop (PLL) design using a 130 nm 2P6M CMOS process. We propose to suppress reference spur through reducing the current mismatch in charge pump (CP), controlling the delay time in phase frequency detector (PFD), and using a smaller VCO gain (KVCO). With a reference frequency of 32.768 MHz, chip measurement results show that the frequency tuning range is 5.7–6.0 GHz, the reference spur is −68 dBc, the phase noise levels are −109 dBc/Hz and −135 dBc/Hz at 1 MHz and 10 MHz offset respectively for 5.835 GHz. Compared with existing designs in the literature, this work’s reference spur is improved by at least 17% and its phase noise is the lowest. Under a 1.5 V supply voltage, the power dissipation with an output buffer of the PLL is 12 mW.  相似文献   

13.
14.
The detection of anti-personnel mines depends on the soil transmission and scattering at a given wavelength. Transmission spectra were measured over the range 90–4200 GHz for 19 soil samples that span a number of soil orders that have extensive worldwide distribution using a vector network analyzer (90–140 GHz) and a Fourier spectrometer (120–4200 GHz). Transmission drops to nearly zero for wavelengths shorter than the characteristic particle size of the sample as a consequence of scattering. This interpretation is supported by a fit to a standard scattering model with physically reasonable fitting parameters. Transmission spectra were also measured for various liquids (90–600 GHz) for possible index matching. These liquids were mixed with the soil sample and were found to reduce scattering and increase transmission through the soil at higher frequencies. This work is relevant to mine detection using terahertz and millimeter wave radiation for high resolution images through the soil.  相似文献   

15.
The aim of this work is to present a vector network analyzer based channel sounding system capable of performing measurements in the range from 2 to 50 GHz. Further, this paper describes an indoor measurement campaign performed at 26–30 GHz. The sounding system is capable of receiving two channels and transmitting one. Using this feature a channel measurement has been performed using both a directional horn antenna and a virtual uniform circular array (UCA) at the same time. This allows for comparative studies of measured channels with two different antennas in a simultaneous way. The measurement has been conducted with 42 measurement positions distributed along a 10 m long path through an indoor laboratory environment. The transmitter was positioned such that measurements were conducted both in line-of-sight and non-line-of-sight scenarios. The measurements showed good agreement between the measurement data collected with the horn antenna and the data collected with the UCA. The propagation environment was found to be sparse both in delay and angular domain for the given scenario. Based on the performed measurement campaign together with validation measurements of the system stability, it is found that the system works as expected.  相似文献   

16.
This letter presents a new current reused LC-tank injection locked oscillator (ILO), which is implemented by using a standard TSMC 0.18-mum CMOS process. The ILO, used as a divide-by-two (divide2) divider, is consisted of two switching transistors stacked in series. The injection locking is performed by adding an injection nMOS between the differential outputs of the divider. The divider can operate with a lower power due to the reuse of dc current. The measurement results show that at the supply voltage of 1.5V, the divider free-running frequency is tunable from 2.11 to 2.42GHz, and at the incident power of 0dBm the locking range of the divider in the divide2 mode is about 0.9GHz (19.8%), from the incident frequency 4.1 to 5GHz. The core power consumption is 0.97mW  相似文献   

17.
The microwave surface resistance, Rs measurement of YBa 2Cu307 (YBCO) thin film deposited on 10 mm × 10 mm LaAlO3 substrate using three prime resonating techniques, namely, cavity end plate substitution technique (20 GHz), dielectric resonator technique (18 GHz), and microstrip resonator technique (5 GHz), is reported. In addition, theoretical analysis for each technique has been performed to calculate the relative percentage error in the measured Rs -value of the YBCO thin film as a function of temperature. It has been found that the shielded dielectric resonator provides far better sensitivity for R.-measurement of the YBCO thin film with minimum relative percentage error (<4%) in the temperature range from 20 K to transition temperature of YBCO thin film compared to the other two techniques  相似文献   

18.
The authors propose the design of one radial line slot antenna with two simultaneous beams, one broadside beam and one conical beam. The antenna is a radial line slot antenna (RLSA), with the slots placed on the upper plate in concentric rings. The radiating element is a slot pair, designed for getting left hand circular polarization. The antenna has been designed to work in the range of 13.4 GHz and 14 GHz. Both beams are obtained independently through very simple excitation circuits, realized with microstrip technology. These feeding networks include a Butler Matrix Network. Comparing both radiation patterns, amplitude and phase, theta and phi angles of arrival direction can be obtained. This monopulse performance can be used to orientate the pencil beam for satellite communication antennas. Measurements for a first prototype are presented to validate the design.  相似文献   

19.
This work presents a single-ended active mixer realized with a 0.13 /spl mu/m BiCMOS SiGeC heterojunction bipolar transistor (HBT) technology. This mixer is designed to be integrated in a superheterodyne receiver for 40 GHz wireless communication systems. Local oscillator (LO) and RF signals are directly applied to the base of the HBT through two coupled lines. The mixer provides a down-conversion from 42 GHz to 2 GHz. The mixer exhibits a power conversion gain better than 2.4 dB and a measured double-sideband noise figure less than 8.3 dB for P/sub LO/=3 dBm (power of the local oscillator) under a global power consumption lower than 9.5 mW. This architecture exhibits good linearity performance with a measured IP/sub 1dB/ of about -7 dBm and an IIP3 of +4 dBm. The linear dynamic range for a 2 GHz system bandwidth is approximately 65 dB for P/sub LO/=+2 dBm and T/sub 0/=290 K. The third order spurious free dynamic range is calculated to be better than 52 dB.  相似文献   

20.
This letter presents a wide-locking range, body-injected, injection locked frequency divider (ILFD) with tunable active inductors (TAIs) and variable division ratio. The ILFD was fabricated in the 0.18 mum 1P6M CMOS technology, and it has the modulus of 2, 3, 4, and 5, and can be used as a first-harmonic injection-locked oscillator (ILO). The divide-by-3 function is performed by injecting differential a signal to the bodies of cross-coupled transistors in the VCO. At the supply voltage of 1.5 V, the free-running divider is tunable from 0.53 to 1.72 GHz. At the incident power of 0 dBm the operation range in the first-harmonic ILO is from the incident frequency 0.53 to 3.2 GHz. The operation range in the divide-by-3 (divide-by-2) mode is about 3.59 (4.13) GHz, from the incident frequency 1.55 to 5.14 (0.87 to 5.0) GHz.  相似文献   

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