A 12-36GHz PHEMT MMIC balanced frequency tripler

A novel configuration of balanced frequency InGaAs pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuit (MMIC) tripler is proposed. A resonant LC filter is used to eliminate the fundamental frequency and a phase delay line is employed to suppress the second harmonic. The separation of the independent phase shifters makes the tripler more compact and flexible. The conversion loss of the tripler operating from 12 to 36GHz is less than 9.4dB at 9-dBm input power. As compared to the third-harmonic frequency, the fundamental frequency is suppressed more than 21.4dB while for the second harmonic is more than 22.3dB at 36GHz.     

Narrow-band modulation of semiconductor lasers at millimeter wavefrequencies (>100 GHz) by mode locking

The possibility of mode locking a semiconductor laser at millimeter wave frequencies approaching and beyond 100 GHz was investigated theoretically and experimentally. It is found that there are no fundamental theoretical limitations in mode locking at frequencies below 100 GHz. At these high frequencies, only a few modes are locked and the output usually takes the form of a deep sinusoidal modulation which is synchronized in phase with the externally applied modulation at the intermodal heat frequency. This can be regarded for practical purposes as a highly efficient means of directly modulating an optical carrier over a narrow band at millimeter wave frequencies. Both active and passive mode locking are theoretically possible     

A Low-Voltage Broadband Feedforward-Linearized BJT Mixer

A low-voltage, feedforward-linearized bipolar mixer realizes an input$hboxIP_3$of$+$14.3 dBm and an input$hboxIP_2$of$+$54.5 dBm at 2.4 GHz. Conversion (power) gain over the 1–6GHz RF input range is 12.4$,pm,$0.35 dB, while the input$hboxIP_3$is 13.6$,pm,$1.8dBm over the same frequency range. The broadband mixer's RF input impedance varies from 60.3-j7.1 at 2.4 GHz to 57.4-j16.6$~Omega$at 5.8GHz. Measured SSB (50$Omega$) noise figure is 18.6 dB at 2.4 GHz. No on-chip inductors are used in the design, and the 0.14$hbox mm^2$(active area) mixer dissipates 7.2 mW from a (minimum) 1.2 V supply.     

A dual-gate 2nd/3rd-order subharmonic injection-locked oscillator in GaAs PHEMT

A dual-gate subharmonic injection-locked oscillator (SILO) has been designed and fabricated in 0.5 μm GaAs PHEMT process for millimeter-wave communication applications. Specifically, this study proposes a dual-gate circuit topology to achieve a high-frequency oscillator with a large output signal power. The proposed dual-gate transistor also performs a wideband negative resistance characteristic by which the self-oscillation frequency can easily be determined with a proper resonator. The measured self-oscillation frequency of the proposed SILO is approximately 49 GHz, and the frequency tuning range is adjustable from 48.7 GHz to 49.7 GHz with an output power of 8 dBm. By injecting a 2nd-order (~24.5 GHz) subharmonic signal into the dual-gate SILO, the maximum locking range of 5.6 GHz can be approached at an input power of 11 dBm without any self-oscillation frequency tuning. With changing the input frequency to be a 3rd-order subharmonic injection (~16.3 GHz), an output locking range of 2.9 GHz also can be achieved. The measured phase noises of the output signals from 2nd- and 3rd-order subharmonic injections are −101 and −100 dBc/Hz, respectively, at 100-kHz offset frequency.     

A CMOS Direct Injection-Locked Frequency Divider With High Division Ratios

A CMOS injection-locked frequency divider (ILFD) with high division ratios and high frequency operation is presented. It consists of a ring oscillator and injection capacitors. An input signal is directly injected through the capacitors into the feedback nodes of the ring oscillator. The proposed ILFD is fabricated in a $0.18~mu{rm m}$ CMOS process and has a chip core size of $68~mu{rm m}times 70~mu{rm m}$. It shows multiple division ratios of 3, 6, and 9. The operation frequency is from 2.2 to 30.95 GHz. At the maximum operation frequency, the ILFD has a locking range of 260 MHz with an input power of less than 0.25 dBm, a division ratio of 9, and a power consumption of 12.5 mW. The locking range increases up to 3.2 GHz as the division ratio and the operation frequency decrease.      

次谐波调制下光注入DFB-LD结构的可调谐光电振荡器

为实现具有高频谱纯度、低相位噪声的宽带可调谐微波信号生成,提出并通过实验验证了一种次谐波信号调制下光注入半导体激光器结构的光电振荡器,其原理为通过利用光注入半导体激光器的单周期（P1）振荡工作状态和波长选择放大特性实现可调微波信号生成,并进一步通过在光电振荡环路中引入次谐波信号调制对系统生成微波信号的频率稳定性、边模抑制比与频谱纯度进行优化。实验结果表明,文中方案提出的光电振荡器可以生成输出功率大于5 dBm,频率调谐范围为12~18 GHz的微波信号。同时,系统生成的微波信号的3 dB带宽为100 kHz,边模抑制比可达 51 dB,且信号在频偏量为100 Hz和10 kHz处的相位噪声分别为?78 dBc/Hz和?109 dBc/Hz。此外,光电振荡器生成微波信号的频率调谐范围只受系统中使用的各类光电器件工作带宽的限制,通过采用具有更大带宽的光电器件可以实现更高频率的微波信号生成。     

Subharmonic synchronous and hybrid mode-locking of a monolithic DBR laser operating at millimeter-wave frequencies

A detailed comparison of subharmonic synchronous and subharmonic hybrid mode-locking of a monolithic distributed Bragg reflector (DBR) laser operating at 33 GHz is presented. Optical injection at the 20th subharmonic frequency (1.65 GHz) has produced a locking range of 10 MHz with negligible amplitude modulation. In comparison, electrical injection at the 4th subharmonic frequency (5.83 GHz) has shown higher levels of amplitude modulation and a narrower locking range (4 MHz). While subharmonic hybrid mode-locking remains a simple and cost effective solution for the generation of low timing jitter high-repetition rate optical pulse trains, subharmonic synchronous mode-locking shows superior performance with regard to reduced amplitude modulation and larger locking range.     

Design and performance of phase reversal traveling wave modulators

A new optimization routine for the design of integrated optic phase reversal traveling wave modulators is demonstrated. The positions of the microwave phase reversal are computed to give a flat frequency response over the required frequency range. Experimental results on a three section periodic phase reversal modulator exhibiting a 7.5-GHz bandpass response centered at 12.75 GHz and a peak phase shift of 0.725 rad at 11.5 GHz for 20-dBm microwave power are presented     

Optical phase modulation in an injection locked AlGaAs semiconductor laser

Optical phase modulation obtained by injecting coherent CW light into a directly frequency-modulated semiconductor laser is reported. Phase modulation at up to a 1 GHz modulation frequency has been obtained without compression for a 1.4 GHz half locking bandwidth. Phase deviation can be represented by the ratio of the original FM deviation to the locking half bandwidth. The phase deviation normalized by the frequency deviation is inversely proportional to the cutoff modulation frequency. A static phase shift of π took place with a 0.48 mA drive current change in the injection locked laser. Reduction in FM noise by means of CW light injection and FM noise accumulation in cascaded injection locked laser amplifiers are discussed, together with the optimum design for an injection locked repeater system.     

Pulsed injection locking dynamics of passively mode-lockedexternal-cavity semiconductor laser systems for all-optical clockrecovery

The performance characteristics of a pulse injection locked, passively mode-locked (PML) external-cavity semiconductor laser system for all-optical clock recovery are investigated in detail. It is important to characterize the clock recovery dynamics to understand the fundamental capabilities and limitations of the clock recovery system. It is experimentally shown that these devices offer robust clock recovery with low phase and amplitude noise, low injected data power requirements, large frequency locking bandwidth, large phase tracking bandwidth, short lockup time, long dephasing time and immunity to bit-pattern-effects. Harmonic clock generation and subharmonic clock generation are demonstrated for data-rate conversion applications     

A harmonic injection-locked frequency divider in 0.18-/spl mu/m SiGe BiCMOS

A harmonic injection-locked frequency divider for high-speed applications is presented in this letter. In order to enhance the bandwidth of the high-order frequency division, a positive feedback is employed in the design of the subharmonic mixer loop. The proposed circuit is implemented in a 0.18-/spl mu/m SiGe BiCMOS process. With a singled-ended super-harmonic input injection of 0dBm, the frequency divider exhibits a locking range of 350MHz (from 59.77 to 60.12GHz) for the divide-by-four frequency division while maintaining an output power of -16.6/spl plusmn/ 0.5dBm within the entire frequency range. The frequency divider core consumes a dc power of 50mW from a 3.6-V supply voltage.     

A Low-Power, High-Suppression V-band Frequency Doubler in 0.13 $mu$ m CMOS

A V-band frequency doubler monolithic microwave integrated circuit with a current re-use buffer amplifier is presented. The circuit is designed and fabricated using 0.13 $mu$m CMOS technology. The buffer amplifier uses a current re-use topology, which adopts series connection of two common source amplifiers for low dc power consumption. The suppression of the fundamental frequency is obtained by shunting the input frequency at the output node of the doubler and the drain nodes of two common-source stages of the buffer amplifier. The fabricated frequency doubler exhibits an output power of ${-}$4.45 dBm and a conversion gain of ${-}$ 0.45 dB at input frequency of 27.1 GHz with an input power of ${-}$4 dBm. The suppression of the fundamental signal is 49.2 dB. The total dc power dissipation is 9 mW while the buffer amplifier consumes 5 mW. The integrated circuit size including pads is 1.24 mm$, times ,$0.75 mm. To our knowledge, this is the highest suppression with low-power dissipation among V-band frequency doublers.      

Millimeter-wave CMOS circuit design

We have developed a 27- and 40-GHz tuned amplifier and a 52.5-GHz voltage-controlled oscillator using 0.18-mum CMOS. The line-reflect-line calibrations with a microstrip-line structure, consisting of metal1 and metal6, was quite effective to extract the accurate S-parameters for the intrinsic transistor on an Si substrate and realized the precise design. Using this technique, we obtained a 17-dB gain and 14-dBm output power at 27 GHz for the tuned amplifier. We also obtained a 7-dB gain and a 10.4-dBm output power with a good input and output return loss at 40 GHz. Additionally, we obtained an oscillation frequency of 52.5 GHz with phase noise of -86 dBc/Hz at a 1-MHz offset. These results indicate that our proposed technique is suitable for CMOS millimeter-wave design     

Optical synchronization of millimeter-wave oscillators fordistributed architecture

A review of various methods of phase and frequency synchronization of active MMIC based transmit/receive modules is presented, and particular emphasis is placed on the synchronization of oscillators through the use of an indirect subharmonic optical injection locking technique. In this approach, the nonlinear behavior of large-signal modulated laser diodes and solid-state oscillators is exploited to extend the bandwidth of the synchronizing link to the millimeter-wave frequency range. Experimental results of the phase and frequency coherency of two 21.5 GHz FET oscillators are reported. Optimum performance is achieved at a subharmonic factor of 1/4, with a locking range of 84 MHz and a phase noise degradation of only 14 dB. The phase coherency measurement of two injection-locked oscillators points to a phase shift, which is introduced as a result of the frequency detuning between the slave and master oscillator signals. A scheme to correct for this phase error is presented     

Optical signal generation at millimeter-wave repetition rates usingsemiconductor lasers with pulsed subharmonic optical injection

A new technique is presented and investigated systematically which generates optical signals at millimeter-wave repetition rates from a semiconductor laser, without the need for an intracavity saturable absorber. Optical pulses are generated from a long-cavity semiconductor laser with a repetition rate equal to its cavity resonant frequency by injecting short optical pulses at one of the cavity resonance subharmonics. A rate-equation model is proposed to explain the mechanism of this subharmonic optical injection method. Optical pulses with repetition rates of 35 and 56 GHz are generated using the proposed scheme from a semiconductor laser with a distributed Bragg reflector and a Fabry-Perot laser diode, respectively. The performance of the generated pulses is also evaluated in terms of detected RF power at the repetition frequencies, the subharmonic suppression ratio, phase noise, and timing jitter as a function of frequency detuning, injected optical power, laser bias current, and, finally, the subharmonic number. It is found that the generated optical pulses exhibit large subharmonic suppression ratio (>17 dB), large locking ranges >400 MHz, low levels of phase noise (~-93 dBc/Hz@10 kHz) and timing jitter (<0.41 ps over 100 Hz to 10 MHz), and large tolerance to variations in operating parameters     

A Wide Locking Range Differential Colpitts Injection Locked Frequency Divider

This letter proposes a new wideband Colpitts injection locked frequency divider (ILFD) and describes the operation principle of the ILFD. The circuit consists of a differential CMOS LC-tank oscillator and a direct injection topology. The divide-by-two ILFD can provide wide locking range, and the measurement results show that at the supply voltage of 2.4 V, the tuning range of the free running ILFD is from 4.46 to 5.6 GHz, about 1.14 GHz, and the locking range of the ILFD is from 8.03 to 11.63 GHz, about 3.6 GHz, at the injection signal power of 0 dBm. The ILFD dissipates 19.92 mW at a supply voltage of 2.4 V and was fabricated in 1P6M 0.18 mum CMOS process. At the tuning voltage of 1.2 V, the measured phase noise of the free running ILFD is -110.8 dBc/Hz at 1 MHz offset frequency from 4.94 GHz and the phase noise of the locked ILFD is -135.4 dBc/Hz, while the input signal power is -4 dBm.     

LiTaO3相位调制器扩频特性的研究

介绍一种利用开关微波信号调制LiTaO3电光晶体．实现对输入光扩频的方法。研究了LiTaO3相位调制器的理论模型．并给出了相应的计算公式。利用公式模拟、计算得到在一定做波功率调制下相位调制器输出的扩频光谱。给出了实际系统的框图，并对实际系统的输出光谱进行测量．得到在不同微波调制功率下的光谱图。对理论计算所得的输出光谱与实际系统的输出光谱进行分析．发现谱线情况较一致．仅对应的微波输入功率有差异．原因是实际系统中微波传输线阻抗不匹配．所需的实际微波功率比理论值大。该系统的电光晶体为LiTaO3．激光器工作波长为1053nm，微波频率为4．3GHz．开关信号是重复频率为1kHz．占空比为4：6的方波。使90％的光功率分散于主峰以及一、二次边频，且一、二次边频的功率近似相等。     

A fully matched high linearity 2-W PHEMT MMIC power amplifier for 3.5 GHz applications

A 2-W monolithic microwave integrated circuit power amplifier, operating between 3.3 and 3.8GHz by implementing AlGaAs/InGaAs/GaAs pseudomorphic high electronic mobility transistor for the applications of wideband code division multiple access, wireless local loop, and multichannel multipoint distribution service, is demonstrated. This two-stage amplifier is designed to fully match 50/spl Omega/ input and output impedances. With a dual-bias configuration, the amplifier possesses the characteristics of 30.4dB small-signal gain and 34dBm 1-dB gain compression power with 37.1% power added efficiency. Moreover, with a single carrier output power level of 24dBm, high linearity with a 43.5-dBm third-order intercept point operating at 3.5GHz is also achieved.     

A new approach for a phase controlled self-oscillating mixer

The analytical and experimental demonstration of subharmonic synchronization and phase shifting of a push-pull self-oscillating mixer is presented for the first time. Inherent high mixing gain of the self-oscillating mixer circuit is exploited to generate a strong signal at the same frequency of the reference signal, which is related to the local oscillator's (LO) phase information. A phase error between this signal and the reference signal is extracted in a phase comparator before phase locking. Analytical modeling of frequency and phase stabilization of the push-pull self-oscillating mixer is presented, which is also experimentally verified for a self-oscillating mixer at 12 GHz. This self-oscillating mixer circuit demonstrates efficient phase locking, 0°-180° continuous phase shifting capability in addition to the reported large locking range (>10 MHz), low close-in to carrier phase noise (<7 dB degradation of a 6 GHz synthesized reference signal), and a high mixer conversion gain (>17 dB at 17 GHz). The demonstrated subharmonic phase locking approach replaces the need for a frequency multiplier or divider before the phase comparator. The synchronized push-pull self-oscillating mixer circuit is applicable to the millimeter-wave frequency distributed transmitters and receivers, where low-loss phase shifting and efficient subharmonic phase and frequency locking are hard to achieve     

The use of saw oscillators to suppress fm noise in local oscillators for on-board satellite applications

SAW oscillators can provide fundamental frequency operation to above 1·5 GHz, with stability and FM noise performance approaching that offered by bulk crystal oscillator technology. Their high fundamental frequency, small size and rugged construction gives SAW technology a unique capability at UHF and microwave frequencies. The low FM thermal noise floor associated with fundamental frequency operation can be combined with the stability and low close-to-carrier noise of multiplied bulk crystal oscillators by locking a high frequency SAW oscillator to a bulk crystal reference. SAW oscillator stability is compatible with conventional phase-locked-loop techniques and also with injection lock stabilization, and their own low close-to-carrier FM noise ensures that such locked sources exhibit minimum phase noise. Furthermore, locked oscillator phase noise is not significantly degraded when extreme operating conditions, such as those experienced in space applications, demand a reduced SAW device Q for reliable locking using either technique. Use of a PLL avoids any need for reference frequency multiplication, and provides additional design flexibility with respect to reference frequency selection and phase noise optimization. Injection locking offers design simplicity and uses fewer frequency control components, which can contribute additional noise in PLL sources.