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Journal ArticleDOI

Investigation of Different Input-Matching Mechanisms Used in Wide-Band LNA Design

15 Feb 2005-International Journal of Infrared and Millimeter Waves (Kluwer Academic Publishers-Plenum Publishers)-Vol. 26, Iss: 2, pp 221-245
TL;DR: The simulated result that both matched input impedance and low noise temperature Tn can be achieved simultaneously over a wide bandwidth in the single-ended low noise amplifier is proved mathematically and is well interpreted.
Abstract: This paper analyzes different input-matching mechanisms used in designing the wide-band amplifiers in general, and the low noise amplifiers (LNA) in particular, and their corresponding noise impact. Among them, the most promising one is the reactive-feedback circuit configuration, which is a combination of high-frequency inductive feedback and low frequency capacitive feedback. In this paper the simulated result that both matched input impedance and low noise temperature Tn can be achieved simultaneously over a wide bandwidth in the single-ended low noise amplifier is proved mathematically and is well interpreted. This understanding of reactive feedback is crucial for the future development of ultra-wide-band low-noise amplifiers.
Citations
More filters
Journal ArticleDOI
TL;DR: The noise figure of the presented LNA is to the authors' knowledge the lowest noise figure achieved by a power matched wideband CMOS LNA at room temperature.
Abstract: This paper presents a wideband low-noise amplifier (LNA) designed to be used as the first stage of the receiver in the Square Kilometer Array radio telescope. The LNA design procedure and its layout features are discussed. The noise figure optimization procedure determines the signal-source resistance that results in reduced noise figure. When used in the radio telescope, the required signal-source resistance will be presented by the telescope custom-made antenna elements. The LNA, designed in 90 nm bulk CMOS, achieves sub-0.2 dB noise figure from 800 MHz to 1400 MHz, return loss of more than 11 dB, gain of more than 17 dB driven into a 50 load, output 1 dB compression point of 2 dBm, output IP3 of 12 dBm, and output IP2 of 22 dBm while consuming 43 mA from a 1 V supply. In the LNA implementation presented in this paper the load choke inductor and the source inductor are integrated whereas the gate-, bias-, and the choke-inductor between two transistors of the cascode are external. The noise figure of the presented LNA is to our knowledge the lowest noise figure achieved by a power matched wideband CMOS LNA at room temperature.

98 citations

Proceedings ArticleDOI
11 Jun 2006
TL;DR: In this article, a 1.5 V, 3/spl sim/11 GHz CMOS UWB LNA using dual feedback loops is reported using shunt capacitive feedback and series transformer feedback.
Abstract: A 1.5 V, 3/spl sim/11 GHz CMOS UWB LNA using dual feedback loops is reported. Using shunt capacitive feedback and series transformer feedback the broadband matching condition is achieved with high flat gain. Fabricated in 0.18 /spl mu/m CMOS process, the measurement result demonstrates power gain of 11 dB and maximum NF less than 5.6 dB throughout the frequency range from 3.1 to 10.6 GHz with power consumption of 10.6 mW.

46 citations


Cites background or methods from "Investigation of Different Input-Ma..."

  • ...The LNA circuit achieves almost the same noise figure level to the minimum noise figure (NFmin) over the entire frequency band of interest....

    [...]

  • ...Recently filter design technique is employed to incorporate the transistor gate-source capacitance as a part of the LC-ladder matching network and greatly extend the bandwidth to a wide range [2], [3]....

    [...]

Journal ArticleDOI
TL;DR: In this paper, a wide-band low-noise amplifier with matched input impedance and low noise temperature over 10-20 GHz is presented, and a bandwidth broadening mechanism using double feedback is also proposed for the future design of matched ultra-wide-band LNA.
Abstract: This paper presents the development of a wide-band amplifier with matched input impedance and low noise temperature over 10-20 GHz. Here, the novel wide-band feedback mechanism provided by the transistor's intrinsic gate-drain capacitor will be analyzed in detail with both the derived input reflection coefficient and noise temperature of the resulting circuit confirmed by their simulated counterparts. It is thus clear why by fine tuning its output RC loading impedance and source inductance, a transistor's input reflection coefficient and noise temperature can be greatly improved over broad bandwidth. To demonstrate the feasibility of this novel approach, a wide-band low-noise amplifier (LNA) is designed and characterized. A bandwidth broadening mechanism using double feedback is also proposed for the future design of matched ultra-wide-band LNA.

32 citations


Cites background from "Investigation of Different Input-Ma..."

  • ...3, the simulated and matched of both the transistor and its corresponding wide-band circuit are displayed....

    [...]

Journal ArticleDOI
TL;DR: The concept of noise matching was introduced in this article, where an LNA is driven by a signal source, the impedance of which is designed to equal the LNA's optimum signal-source impedance for minimum noise, or Zopt.
Abstract: Researchers have described the concept of noise matching since at least the 1950s [1]-[4], with studies demonstrating the interrelationships among the noise factor of a low-noise amplifier (LNA), the LNA's noise parameters, and the signal-source impedance Zs. Noise matching is accomplished when an LNA is driven by a signal source, the impedance (or admittance) of which is designed-perhaps using a matching network-to equal the LNA's optimum signal-source impedance for minimum noise, or Zopt. The complex Zopt = Gopt + jXopt represents two of the four noise parameters that completely characterize the noise behavior of a linear two-port device, such as an LNA. The other two noise parameters are the minimum noise factor, Fmin , and the Lange invariant N [5], [6], which is, arguably, a more fundamental parameter than the often-used equivalent noise resistance, Rn.

22 citations


Additional excerpts

  • ...To reduce the number of lossy reactive parts at the LNA input, the inherent feedbackthrough-transistor gate-drain capacitance has also been employed to tune the power match independently of the noise match [50], [54]–[59]....

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Patent
24 May 2006
TL;DR: In this paper, a low-noise amplifier for ultra broad-band wireless communication is proposed, which is able to provide optimal conditions for broadband input impedance matching and broadband noise optimum, besides significantly increasing the gain and gain flatness, there are also huge improvements to the noise performance and the cost-down on fabrication.
Abstract: This invention relates to a low noise amplifier, used in radio frequency integrated circuit design, especially low noise amplifiers for ultra broad-band wireless communication, comprising at least a transistor of the core circuit of a low noise amplifier structure, a transformer that is implemented on the chip, in order to form a dual feedback amplifier, that is, an amplifier structure comprising an inductive feedback and a capacitive feedback, wherein the capacitive feedback is used for the low and medium frequency range, while the inductive feedback is used for the high frequency range. By assembling an amplifier circuit with these two feedback paths, it is possible to provide a broadband and good impedance matching at the signal input end of the circuit. The low noise amplifier circuit structure of the present invention is able to provide optimal conditions for broadband input impedance matching and broadband noise optimum; besides significantly increasing the gain and gain flatness, there are also huge improvements to the noise performance and the cost-down on fabrication, and the energy consumption can also be maintained at a very low level.

13 citations

References
More filters
Journal ArticleDOI
TL;DR: In this article, a method to determine the small-signal equivalent circuit of FETs is proposed, which consists of a direct determination of both the extrinsic and intrinsic small signal parameters in a low-frequency band.
Abstract: A method to determine the small-signal equivalent circuit of FETs is proposed This method consists of a direct determination of both the extrinsic and intrinsic small-signal parameters in a low-frequency band This method is fast and accurate, and the determined equivalent circuit fits the S-parameters well up to 265 GHz >

1,491 citations

Journal ArticleDOI
Marian Pospieszalski1
TL;DR: In this article, a simple noise model of a microwave MESFET (MODFET, HEMT, etc.) is described and verified at room and cryogenic temperatures.
Abstract: A simple noise model of a microwave MESFET (MODFET, HEMT, etc.) is described and verified at room and cryogenic temperatures. Closed-form expressions for the minimum noise temperature, the optimum generator impedance, the noise conductance, and the generator-impedance-minimizing noise measure are given in terms of the frequency, the elements of a FET equivalent circuit, and the equivalent temperatures of intrinsic gate resistance and drain conductance to be determined from noise measurements. These equivalent temperatures are demonstrated in the case of a Fujitsu FHR01FH MODFET to be independent of frequency in the frequency range in which 1/f noise is negligible. Thus, the model allows prediction of noise parameters for a broad frequency range from a single frequency noise parameter measurement. The relationships between this approach and other relevant studies are established. >

707 citations

Journal ArticleDOI
TL;DR: In this article, four reported low-noise amplifier (LNA) design techniques applied to the cascode topology based on CMOS technology are reviewed and analyzed: classical noise matching, simultaneous noise and input matching (SNIM), power-constrained noise optimization, and power-consistency with SNIM (PCSNIM) techniques.
Abstract: This paper reviews and analyzes four reported low-noise amplifier (LNA) design techniques applied to the cascode topology based on CMOS technology: classical noise matching, simultaneous noise and input matching (SNIM), power-constrained noise optimization, and power-constrained simultaneous noise and input matching (PCSNIM) techniques. Very simple and insightful sets of noise parameter expressions are newly introduced for the SNIM and PCSNIM techniques. Based on the noise parameter equations, this paper provides clear understanding of the design principles, fundamental limitations, and advantages of the four reported LNA design techniques so that the designers can get the overall LNA design perspective. As a demonstration for the proposed design principle of the PCSNIM technique, a very low-power folded-cascode LNA is implemented based on 0.25-/spl mu/m CMOS technology for 900-MHz Zigbee applications. Measurement results show the noise figure of 1.35 dB, power gain of 12 dB, and input third-order intermodulation product of -4dBm while dissipating 1.6 mA from a 1.25-V supply (0.7 mA for the input NMOS transistor only). The overall behavior of the implemented LNA shows good agreement with theoretical predictions.

542 citations

Journal ArticleDOI
TL;DR: In this paper, a method to determine the broadband small-signal equivalent circuit of field effect transistors (FETs) is proposed based on an analytic solution of the equations for the Y parameters of the intrinsic device and allows direct determination of the circuit elements at any specific frequency or averaged over a frequency range.
Abstract: A method to determine the broadband small-signal equivalent circuit of field-effect transistors (FETs) is proposed. This method is based on an analytic solution of the equations for the Y parameters of the intrinsic device and allows direct determination of the circuit elements at any specific frequency or averaged over a frequency range. The validity of the equivalent circuit can be verified by showing the frequency independence of each element. The method can be used for the whole range of measurement frequencies and can be applied to devices exhibiting severe low-frequency effects. >

357 citations

Journal ArticleDOI
TL;DR: In this paper, the authors describe a two-stage InP-based amplifier with a gain of 27 dB and a noise temperature of 31 K with a power consumption of 14.4 mW per stage, including bias circuitry.
Abstract: This paper describes cryogenic broad-band amplifiers with very low power consumption and very low noise for the 4-8-GHz frequency range. At room temperature, the two-stage InP-based amplifier has a gain of 27 dB and a noise temperature of 31 K with a power consumption of 14.4 mW per stage, including bias circuitry. When cooled to 15 K, an input noise temperature of 1.4 K is obtained at 5.7 mW per stage. At 0.51 mW per stage, the input noise increases to 2.4 K. The noise measurements have been repeated at different laboratories using different methods and are found consistent.

146 citations