https://www.ijedr.org/download.php?file=IJEDR1502195.pdf

Rudimentary Study and Design Process of Low Noise Amplifier At Ka Band

The design method of an X band broadband low noise amplifier composed of three stages pHEMT FETs is introduced in this paper.The X Band broadband low noise amplifier with 0.25um GaAs pHEMT technology is realized.The measured results show: single power is +5V,frequency range covers 6~11.5GHz,Gain is more than 29.5dB,and noise factor is less than 1.7dB.Having characters of wide bandwidth,low noise-factor,high gain and single +5V power supply etc,the chip is especially suitable for using in T/R modules of large-scale phased array radar.

Design of X-Band Broadband Low Noise Amplifier MMIC

A Ka-band two-stage low noise amplifier(LNA) monolithic microwave integrated circuit(MMIC) has been developed.The gate width of the active device and the source series feedback are chosen carefully to minimize the distance between Γo and S*11,where Γo is the load impedance providing the minimum noise figure and S*11 is a conjugate reflection coefficient of S11,and then the LNA can achieve optimal noise match and conjugate match simultaneously.Also the source series feedback can increase the stability of the LNA.The amplifier that is fabricated by a commercial 0.18μm pseudomorphic high electron-mobility transistor(pHEMT) has achieved a gain of more than 10dB in the frequency range of 29 to 33 GHz and a noise figure of 2.3 dB at 30 GHz.The chip size is 1.4×0.9mm2.

The Design of a Ka-band Low Noise Amplifier MMIC

Communication industry is currently in continuous growth..In recent time for satellite communication, spectrum at C-band and Ku band is almost congested and for various new applications Ka band is being explored. In particular the Very Small Aperture Terminal [VSAT] networks have gained wide use for business and private applications. Power Amplifier [PA] is important block in transmitter section. Various amplifier configuration were studied and suitable configuration was selected. Also design steps for power amplifier were understood. After Literature survey and studying different transistor, a suitable for Power Amplifier at centre frequency 29.5 GHz over 100 MHz bandwidth for Very Small Aperture terminal at Ka band will be designed. Its performance will be evaluated based on certain parameters like Gain, Efficiency, 1 dB compression point [P1dB], 3rd order intercept point [TOI] and it will be simulated using Advance Design System [ADS]. KeywordsVSAT, PA, P1dB, TOI, ADS. 1. INRODUCTION An amplifier get a signal from some pickup transducer or other input source and provide a larger version of the signal to some output device or to another amplifier stage. An input transducer signal is mostly small and need to be amplified sufficiently to operate an output device. In small signal amplifier, the main factors are usually amplification linearity and magnitude of gain. Because of signal voltage and current are small in small-signal amplifier and the amount of power handling capacity and power efficiency are of little concern. On the other side Large-signal amplifiers or power amplifiers used to provide sufficient power to an output load to drive output device typically few watts to ten watts. The main feature of power amplifier is the circuit’s power efficiency, the maximum output power that the circuit is capable of handling and the impedance matching to the output device. . PA is designed to meet a number of indicators such as noise figure, gain and input VSWR. Because of the calculation process is more complex, we usually make it by CAD technology. In this paper, we make the simulation and optimization of the circuit through the ADS microwave circuit simulation design software which greatly help us shorten the design cycle and improve design efficiency. Due to significant R&D funding, innovations, processing advancement and electronic circuit developments, the Microwave Monolithic Integrated Circuit(MMIC) has now become commonplace, replacing many discrete circuits with individual transistors, resistors, capacitors, inductors and element interconnections. MMIC circuits show reduced size and cost with higher reliability to meet the needs of today’s markets. The pHEMT has outstanding high-frequency characteristics, power characteristics and low-noise characteristics, and it is one of the most competitions in the field of microwave and millimeter-wave monolithic integrated circuits. The low power amplifier is the key component in transmitter section, which dictates the dynamic range of the transmitter. MMIC LNAs with Low noise, high gain, good return loss, low power dissipation, high reliability and compact size are required aggressively for many system applications . 2. THE PRINCIPLES OF AMPLIFIER DESIGN Fig. 1 Block dia. of amplifier A single-stage microwave transistor amplifier can be modeled by the fig 1. Here matching network is used on both sides of the transistor to transform the input and output impedance Z0 to the source and load impedances ZS and ZL. Matching circuit is used to avoid unnecessary loss of power. Reflections are eliminated on the transmission line, this procedure is referred to as tuning. A. DC BIASING Biasing a Transistor amplifier is the process of setting the dc (Biasing) operating voltage and current to the correct level so that any ac input signal can be amplified correctly by the transistor. That is by setting its Collector current (Ic) to a steady state value without an input signal applied to the transistors Base, and by the values of the dc supply voltage (Vcc) and the value of the April 2015, Volume 2, Issue 4 JETIR (ISSN-2349-5162) JETIR1504031 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 1021 biasing resistors connected the transistors Base terminal. The goal was to select an operating point that would give sufficient output power, have relatively low noise, and operate in the class A region. The correct bias Operating point of the transistor is generally somewhere between the two extremes of operation, that is halfway between cutoff and saturation. This mode of operation allows the output current to increase and decrease around the amplifiers Q-point without distortion as the input signal swings through a complete cycle. B. STABILITY FACTOR Amplifier is not reliable when it is instable condition. The stability of a circuit is characterized by stern stability factor. The circuit is stable only when K > 1 and Δ< 1. When the input and output reflection coefficients are less than one then we determined the absolute stability factor: C. IMPEDANCE MATCHING Impedance matching at input and output port done by using smith chart technique, by properly adjusting the value of inductance and capacitance at input and output side, we have managed to match impedance with the terminating resistance of 50 Ω. ΓS and ΓL is the source and load reflection coefficient respectively. Input and output reflection coefficient is Γin and Γout respectively shown in following equations: D. S-PARAMETERS It is refers to RF output voltage verses input voltage in the RFIC and describes the relationship between the two or more port network. In the term of RFIC, S11 and S22 is called reflections coefficient. S21 and S12 are called transmission coefficient. S11 and S22 are used to calculate the input and output reflection in the circuits. S21 and S12 are used to calculate the forward and reverse voltage gain in dB as shown in the figure 2. S-parameter is one of the important parameter of low noise amplifier. Fig. 2 S-parameters of two port network E. Efficiency: The power amplifier is generally the primary consumer of DC power in most hand-held wireless devices, thus amplifier efficiency is an essential consideration. One measure of amplifier efficiency is the ratio of RF output power to DC input power, η =Pout/PDC One drawback of this definition is that it does not account for the RF power delivered at the input to the amplifier. Since most power amplifiers have relatively low gains, the efficiency of this equation tends to over rate the actual efficiency. A better measure that includes the effect of input power is the power added efficiency, given as ηPAE=PAE=(Pout−Pin)/PDC= (1 −1/G)Pout/PDC = (1 −1/G )η April 2015, Volume 2, Issue 4 JETIR (ISSN-2349-5162) JETIR1504031 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 1022 F. RETURN LOSS The characterization of the input and output signal can be shown in more convenient way in the form of return loss when a load is mismatched. This means that all the source power is not delivered to the load. This loss of power is known as “return loss” and can be represented as:

Rudimentary Study and Design Process of Power Amplifier at Ka Band

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Design and Simulation of Power Amplifier at Ka Band

Based on the working mechanism of GaN components and monolithic microwave integrated power amplifiers, a four-stage and four-channel power amplifier design scheme has been realized by simulation in the paper. The physical structure of the GaN HEMT is proposed. Then DC and RF characteristics of the device are simulated in Silvaco. The S-parameters are extracted to design a power amplifier circuit in ADS according to the structure and electric performance of the HEMT. The results show that the output power of the amplifier circuit can reach 5.6W and the power gain is 21dB at 35GHz under CW condition. The PAE of the whole circuit is about 20%. Therefore, this power amplifier can be applied to Ka-band.

Design of a Ka-band GaN HEMT power amplifier based on simulation

The HEMT model in this article is applied by OMMIC D01PH. In this article we design a five circuit, the first two levels are designed for minimum noise and the last three for maximum gain design. The center frequency of this design is 35 GHz with 6 GHz bandwidth, gain is greater than 30dB and the noise figure is less than 3dB. This article describes a Ka-band low-noise amplifier design idea. In this idea we put up two options for the bias circuit design, one is drain supply by a single power and the other is dual-power supply for the drain and gate. We make circuit design and simulation for each program and the simulation results were analyzed and compared.

Design of 8mm Ka-band broadband LNA

A GaN power amplifier which can be applied to Ka-band is simulated and studied in the paper. Based on typical AlGaN/GaN HEMT (high electron mobility transistor) pattern, the transistor model is set up by the Silvaco TCAD. The on-chip spiral inductor and metal-insulator-metal (MIM) capacitance are also simulated in HFSS respectively. Extracted from the modal above, s-parameters are used to design a power amplifier circuit. The final result shows that the output power can reach 21.4dBm and PAE is 18% with 25V bias voltage and 9mA static output current at 35GHz when the input power is 10dBm.

Design of a power amplifier based on GaN HEMTs at Ka-band

A third-harmonic circuit is proposed by using GaAs PHEMT at W-band in the paper. The circuit mainly consists of the power amplifier drive unit and frequency multiplier unit. First, the frequency multiplier circuit is designed which can realize third-harmonic amplifying by taking advantage of strong non-linear characteristics of devices. Then the power amplifier including three-stage and two-channel devices is completed which is used to provide enough input signal for the latter frequency multiplier circuit. Finally the whole circuit is formed combining the two units into together and the output signal is obtained through the band-pass filter at W-band. The simulation result shows that the output power may reach 5dBm at 105GHz when the input power is 10dBm at 35GHz.

A kind of third-harmonic circuits based on GaAs PHEMT at W-band

This paper presents a 94GHz sub-harmonic mixer based on quartz substrates, using GaAs Schottky diodes for harmonic mixing. The transitions and filters are designed and optimized with HFSS. The circuit including the anti-parallel diode pair, matching networks and other HFSS-simulated results was optimized with ADS. In the situation of RF frequency is 89–99 GHz, LO frequency is 49.5GHz, power is 13dBm, the best conversion loss of sub-harmonic mixer is 3.6 dB and the worst conversion loss is 8.9 dB which is shown in the test. The isolations between the three ports are better than 20dB.

Chao Yue

Papers

Design of a Ka-band GaN HEMT power amplifier based on simulation

Design of 8mm Ka-band broadband LNA

Design of a power amplifier based on GaN HEMTs at Ka-band

A kind of third-harmonic circuits based on GaAs PHEMT at W-band

Design of a W-band sub-harmonic mixer based on quartz substrates