Self-oscillating Mixer Research Articles

Self Oscillating Mixer with Dielectric Resonator for Low Noise Block Application

In this paper, the development of a self oscillating mixer (SOM) as part of a low noise block (LNB) for a satellite television receiver is investigated numerically and experimentally. In contrast to other mixers, the developed SOM requires no separate local oscillator as it generates own local oscillator signal. The SOM is developed using a monolithic microwave integrated circuit (MMIC) comprised of two bipolar transistors coupled as a Darlington pair and a dielectric resonator to establish a local oscillator signal. The SOM is designed to oscillate at 3.62GHz driven from 50 W signal generator. The prototype of SOM is fabricated on a dielectric substrate of glass-reinforced hydrocarbon/ceramic lamination (RO4350B) board which has a thickness of 0.762mm and relative permittivity of 3.66. The prototype is then characterized experimentally and exhibits a conversion gain of 8dB with the input and output voltage standing wave ratio (VSWR) less than 2 across the 2520MHz to 2670MHz operating frequency band .

A Low-Noise Self-Oscillating Mixer Using a Balanced VCO Load

A low-noise self-oscillating mixer (SOM) operating from 7.8 to 8.8 GHz is described in this paper. Three different components, the oscillator, the mixer core, and the LNA transconductor stage are assembled in a stacked configuration with full dc current-reuse from the VCO to the mixer to the LNA. The LC-tank oscillator also functions as a double-balanced IF load to the low-noise mixer core. A theoretical expression is given for the conversion gain of the SOM taking into account the time-varying nature of the IF load impedance. Measurements show that the SOM has a minimum DSB noise figure of 4.39 dB and a conversion gain of 11.6 dB. Its input P1 dB is - 13.6 dBm and its output P1 dB is - 2.97 dBm, while its IIP3 and OIP3 are - 8.3 dBm and + 3.3 dBm respectively. The chip consumes 12 mW of dc power and it occupies an area of 0.47 mm2 without pads.

Self-Oscillating Mixer(SOM) With 0.18 μm CMOS Technology

self-oscillating mixer is introduced in this paper, with fundamental signal generated by the oscillator subcircuit in the process of mixing. The oscillator core consumes 3 mA of the current from a 1.8 V DC supply and leads to an output power of –0.88 dBm per oscillator, and a measured phase noise of –91, –102 and –107 dBc/Hz at 100 KHz, 600 KHz and 1 MHz from the carrier, respectively. The proposed mixer achieved IIP3 of 0 dBm in the process of mixing, with conversation gain of 1.93 dB. Designing and simulation the circuit was done in 0.18 μm CMOS technology by ADS2010.

A Millimeter-Wave Self-Oscillating Mixer Using a Mode-Locked Laser

This paper presents a study of millimeter-wave optoelectronic downconversion using the self-oscillating mixer concept. Baseband data are transmitted using a 40-GHz electrical carrier; however, detection only requires a much lower speed photodiode. Both homodyne and heterodyne configurations are presented with the former requiring injection locking which can limit the maximum baseband data rate.

Design of high‐gain wide‐band harmonic self‐oscillating mixers

AbstractIn this work, a new design method is presented for the design of wide‐band harmonic self‐oscillating mixers (HSOM) with high conversion gain. The optimum design for the HSOM circuit is obtained using bifurcation analysis‐ and control‐techniques in combination with nonlinear optimization techniques based on the use of an auxiliary generator. The design method is illustrated through the design of an 11.25–1.5 GHz third harmonic self‐oscillating mixer (3HSOM) with a 6.5 dB down‐conversion gain over a 1.6 GHz bandwidth. It is also demonstrated how the frequency variation of the conversion gain can be shaped by means of the use of bifurcation control techniques. A good agreement between the simulated and experimental results has been found. Copyright © 2009 John Wiley & Sons, Ltd.

30 GHz CMOS Self-Oscillating Mixer for Self-Heterodyne Receiver Application

A 30 GHz CMOS-based self-oscillating mixer (SOM) is demonstrated for millimeter-wave self-heterodyne receiver applications. When injection-locked by transmitted LO carrier, the SOM provides constant and sufficient LO power for mixing process independent of transmitted LO power level. The SOM based on the cross-coupled VCO architecture is realized in 0.13 ?m CMOS process. It has down-conversion loss of about 30 dB and requires the minimum LO injection power of - 32 dBm.

A Millimeter-Wave Sub-Harmonic Self-Oscillating Mixer Using Dual-Mode Substrate Integrated Waveguide Cavity

This paper presents a novel sub-harmonic self-oscillating mixer (SOM) topology that makes use of the transmission characteristics of two operating modes in a substrate integrated waveguide (SIW) cavity. The SOM circuit consists of a dual-mode SIW bandpass filter, a common source heterojunction field-effect transistor, and a low-pass filter. The fundamental mode ( H 101) of the SIW cavity is used for RF mode operation, while the H 202 mode is used for local oscillation. A K a-band experimental prototype has been designed and fabricated to demonstrate and validate our proposed circuit concept. The measured power levels of the self and second harmonic local oscillator signals are about 8.5 and -3 dBm, respectively. The mixer, implemented as a down-converter, achieves a 12-dB conversion loss and an IF phase noise of -81 dBc/Hz at 100-kHz offset with a 34-GHz RF input.

A Dual-Band Self-Oscillating Mixer for $C$-Band and $X$-Band Applications

A self-oscillating mixer that employs both the fundamental and harmonic signals generated by the oscillator subcircuit in the mixing process is experimentally demonstrated. The resulting circuit is a dual-band down-converting mixer that can operate in <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</i> -band from 5.0 to 6.0 GHz, or in <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i> -band from 9.8 to 11.8 GHz. The oscillator uses active superharmonic coupling to enforce the quadrature relationship of the fundamental outputs. Either the fundamental outputs of the oscillator or the second harmonic oscillator output signals that exists at the common-mode nodes are connected to the mixer via a set of complementary switches. The mixer achieves a conversion gain between 5-12 dB in both frequency bands. The output 1-dB compression points for both modes of the mixer are approximately -5 dBm and the output third-order intercept point for <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</i> -band and <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i> -band operation are 12 and 13 dBm, respectively. The integrated circuit was fabricated in 0.13-¿m CMOS technology and measures 0.525 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> including bonding pads.

Analysis of Phase Distribution Errors in Mutually Coupled Harmonic Self-Oscillating Mixers

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The phase error distribution caused by the selection of the working point and synchronization characteristics of an array of mutually coupled harmonic self-oscillating mixers (HSOMs) in a receiving topology is studied using simplified models and a nonlinear analysis. The influence in the phase error of the synchronization phase and the mismatches between the free-running and synchronization frequencies are studied separately. A 4 <formula formulatype="inline"> <tex Notation="TeX">$\times$</tex></formula> 1 element array based on injection-locked and mutually coupled HSOMs has been manufactured for the experimental validation of the simulated results. </para>

Receiving Phased Antenna Array Based on Injection-Locked Harmonic Self-Oscillating Mixers

A 4 times 1 element receiving phased antenna array is presented with phase-shifter elements based on injection-locked harmonic self-oscillating mixers. Each phase-shifter element provides the double functionality of variable phase-shifter and down-converter. The phase-shifts applied to the input signals coming from the different antenna patch elements can be selected by dc control signals in a continuous range of 450deg. The required dc control voltages are calculated for the different incident angles by means of harmonic balance simulations. The influences of phase-shift and conversion gain errors on the beam-steering frequency performance of the antenna are studied. Also illustrated is how the phase-shifter parameters can be optimized in order to minimize the frequency scanning. A 4 times 1 element receiving phased antenna array, with an input frequency band centered at 11.25 GHz and the output frequency band centered at 1.5 GHz, has been manufactured for the experimental validation of the simulated results. A beam scanning range from -23deg to 23deg has been experimentally obtained.

Ultra-high-order self-oscillating mixers based on multiple-element technique

Novel design approaches for ultra-high-order subharmonic self-oscillating mixers (SOMs) based on a multiple-element technique are presented. They are of high impact for high-end millimetre-wave systems as subharmonic operation reduces local oscillator frequency requirements. An outline of the basic theory and a design procedure for arbitrary high mixing orders are presented, and a sixth-order SOM is fabricated for the first time. The prototype exhibits a conversion gain of +2.8 dB at an RF input frequency of 7.4 GHz.

Self-Oscillating Harmonic Opto-Electronic Mixer Based on a CMOS-Compatible Avalanche Photodetector for Fiber-Fed 60-GHz Self-Heterodyne Systems

A self-oscillating harmonic opto-electronic mixer based on a CMOS-compatible avalanche photodetector for fiber-fed 60-GHz self-heterodyne systems is demonstrated. The mixer is composed of an avalanche photodetector fabricated with 0.18-mum standard CMOS process and an electrical feedback loop for self oscillation. It simultaneously performs photodetection and frequency up-conversion of photodetected signals into the second harmonic self-oscillation frequency band. The avalanche photodetector and the mixer are characterized and analyzed, and the RF avalanche multiplication factor is investigated. In addition, conversion efficiency as well as internal conversion gain is determined, and bias conditions are optimized for the best self-oscillating harmonic opto-electronic mixer performance. Data transmission of 5-MS/s 32 quadrature amplitude modulation signals using self-oscillating harmonic opto-electronic mixer is successfully demonstrated.

Nonlinear Analysis of Mutually Coupled Harmonic Self-Oscillating Mixers

In this paper, a phase array based on coupled harmonic self-oscillating mixers (HSOMs) is presented for its application in a receiving antenna array. Nonlinear analysis is realized in a 4 x 1 element array based on injection-locked and mutually coupled HSOMs. Each element of the phase array provides the double functionality of variable phase shifters and downconverters. The ranges of synchronized operation and the corresponding phase shifts provided by the individual HSOMs are analyzed versus the circuit parameters. The phase variation of the coupled HSOMs is calculated for different operation points of the innermost HSOMs of the array. A 4 X 1 element array has been manufactured for the experimental validation of simulated results.

A 5-GHz Subharmonic Injection-Locked Oscillator and Self-Oscillating Mixer

This paper presents a multifunctional circuit realizing the functions of oscillation, mixing, amplification, and frequency multiplication at 5 GHz. A theoretical and experimental description of the circuit is given. The proposed circuit, which combines both the injection-locking and mixing processes, uses only one port where both the RF/intermediate frequency signal and the injection signal (IS) are applied. The IS, which is used to stabilize the oscillation, is at a subharmonic of the oscillation frequency (omegaosc/4) having a power level as low as -50 dBm. Calculations of the phase noise and measurements of the mixing properties are reported which indicate a noise improvement, and a high up-conversion gain. The implementation of the circuit exhibits an up-conversion gain of 14 dB, a phase noise of -110 dBc/Hz at 100-kHz offset, a dB of -15 dBm, a third-order intercept point of -2 dBm, and a power consumption of 35 mW. Calculated and measured results are in good agreement for all cases, emphasizing the relevance of the proposed circuit.

Nonlinear Optimization of Wide-Band Harmonic Self-Oscillating Mixers

A new optimization method is presented for the design of wide-band harmonic self-oscillating mixers (HSOMs). High conversion gain is obtained through near-bifurcation operation and optimization of the harmonic content of the self-oscillation. Bifurcation analysis- and control-techniques are used in combination with nonlinear optimization techniques based on the use of an auxiliary generator. An 11.25-1.5 GHz third harmonic self-oscillating mixer (3HSOM) with a 2.5 dB down-conversion gain over a 1.2 GHz bandwidth has been designed. A good agreement between the simulated and experimental results has been found.

Use of mutually coupled harmonic self-oscillating mixers for receiving phased-array antennas

A topology based on mutually coupled harmonic self-oscillating mixers for beam steering purposes in a receiver configuration is presented. The use of harmonic self-oscillating mixers increases the maximum inter-element phase-shift allowing greater steering angles. A 3 times 1 array has been manufactured showing good agreement between experimental and simulated results.

Integrated Heterojunction Bipolar Transistor Optically Injection-Locked Self-Oscillating Opto-Electronic Mixers for Bi-Directional Fiber-Fed Wireless Applications

A 30-GHz-band third harmonic optically injection-locked self-oscillating opto-electronic mixer is implemented with a 10-GHz InP heterojunction bipolar transistor monolithic microwave integrated circuit oscillator. The monolithic self-oscillating mixer can be optically injection locked in wide operating conditions and can perform efficient frequency up- and down-conversion with low-power optical local-oscillator signals. Using the mixer, bi-directional transmission of 32 quadrature amplitude modulation data in a 30-GHz fiber-fed wireless link is successfully demonstrated.

Integrated Receiver Based on a High-Order Subharmonic Self-Oscillating Mixer

In this paper, a novel integrated receiver front-end at 5.8 GHz using a high-order subharmonic balanced self-oscillating mixer (SOM) with a high conversion gain of 11.1 dB is presented, to the authors' knowledge, for the first time. SOMs are excellent choices for a low-cost receiver design as both the oscillating source and the mixer are combined in one single device. Moreover, the presented structure is of high interest for high-end millimeter-wave systems, as subharmonic operation reduces local oscillator (LO) frequency requirements. The balanced concept of the shown circuit offers inherent RF-LO isolation, lower AM noise, and easy suppression of harmonics. In this paper, the design and performance results of the complete receiver structure are presented both with simulation and measured results and a circuit design model is also developed.

Design and analysis of a microwave large-range variable phase-shifter based on an injection-locked harmonic self-oscillating mixer

In this letter, a new microwave variable phase-shifter based on an injection-locked harmonic self-oscillating mixer, is presented for its application in an active microstrip phased antenna array. The circuit provides the double functionality of variable phase-shifter and down-converter. Maximum conversion gain is obtained, through the optimization of a new multi-harmonic load at the input-port of the circuit. The ranges of synchronized operation are analyzed versus the circuit parameters and the corresponding phase-shifts are calculated. The stability of the synchronized solutions is analyzed using the envelope transient simulation method. An 11.25-1.5-GHz down-converter with a 3.25-GHz free-running frequency has been designed, providing a phase-shift variation at intermediate frequency up to 540/spl deg/, with a 4.5-dB conversion gain. A good agreement between the simulated and experimental results has been found.

Phase-shifter/down-converter cell for phased-array antennas

A circuit based on an injection-locked second harmonic self-oscillating mixer is presented. The circuit provides the double functionality of variable phase shifter and down-converter. Conversion gain can be selected through the optimisation of a multiharmonic load. Phase-shift variation up to 360° at intermediate frequency is obtained through synchronised operation.