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Underwater unmanned detector has been the crux to the exploration and exploitation of marine resources. With the development of undersea vehicles especially Autonomous Underwater Vehicle, higher and higher petitions of intelligent control and autonomous navigation are asked. The autonomous planning of AUV consists of two parts: one is the global path planning on the basis of the known environmental information; the other is the local planning for obstacle avoidance based on sensor data. This paper presents a QPSO algorithm with particle's taxonomic evolution, and designs AUV autonomous planning simulation software on the basis of QT development platform. For the known environment, we establish the annular space optimization model, adjust the velocity and heading of AUV to avoid obstacle by optimization algorithm. A method of the local planning for obstacle avoidance is proposed based on sensor detection window for unknown obstacles. The effectiveness of the proposed method is demonstrated by simulation.

A method for multi-mode stability analysis of power amplifier is presented which does not demand strict circuit symmetry. Transformation from n-port signals to n-mode signals is used to provide the oscillating signal's “mode” information which allows the circuit designer to find the instability source and to adopt suitable methods for circuit stabilization. The proposed method has been applied to a four-branch combining power amplifier circuit to verify its effectiveness.

A novel method of full phase-coherent synthesis is proposed in this paper, which uses the frequency-converting technology and the phase-locked loop to fulfill the transmission and tracking of the frequency and phase between the main loop and secondary loops. This method, which differs from the traditional converting-filtering scheme, can solve the tradeoff between the frequency difference and the bandwidth of the full phase-coherent outputs, and it can have a high isolation between the outputs. A Ka-band full phase-coherent frequency synthesizer is implemented based on the idea. The measured results show that this novel full phase-coherent frequency synthesis method proposed in this paper is correct. The frequency synthesizer has full phase-coherent characteristics along with a very low phase noise, fast hopping time, high spurious rejection, and very high isolation between the main output and the secondary output.

This paper demonstrates an active single-balanced mixer with InP double heterojunction bipolar transistor (DHBT) process for direct down-conversion system at 89 GHz. Authors use Coplanar Waveguide (CPW) as on-chip transmission line and tune an on-chip CPW balun to allocate LO signal to the switch cell. Benefiting from its balanced structure, this mixer shows a LO port to RF port isolation above 20 dB in all W-band. Its conversion gain is up to 3 dB with a 3 dB RF bandwidth more than 10 GHz. With a 10 dBm LO signal, the RF input 1 dB compression point is higher than −4 dBm around 89 GHz. This mixer consumes 340 mW power with a +4 V supply. All wafers have been thinned to 100 um before measurements.

This paper presents an initial design of a single-ended gate mixer in self-developed InP High Electron Mobility Transistor (HEMT) technology and its critical parameters measured from 75 GHz to 110 GHz. This mixer realizes a fair conversion loss between 8 dB to 14 dB in full W-Band both in up and down conversion mode, and a 1-dB input compression points more than 0 dBm with the LO pumped at 89 GHz or 94 GHz. All measurement results above are illustrated and analyzed briefly. In a conclusion, it demonstrates the potentials and possibilities to develop passive mixers in W-Band with this process in more complicated structures.

This paper presents a 79 GHz sub-harmonic mixer (SHM) design based on a self-developed 1 um InP DHBT process. In this design, a low frequency local oscillator (LO) input signal at 39.5 GHz is doubled to W-band and a radio frequency (RF) signal ranging from 80 GHz to 86 GHz is down-converted to the intermediate frequency (IF) band with a best conversion gain around 1 dB at 83 GHz. As the knowledge of authors, it is the first attempt to implement an InP DHBT based SHM with a LO doubler in W-band. Due to lacking of available RF sources, the testing is realized with one port of an output power fixed Vector Network Analyzer enhanced by a frequency up-conversion module.

A full W-band low noise amplifier (LNA) module is designed and fabricated. A broadband transition is introduced in this module. The proposed transition is designed,optimized based on the results from numerical simulations. The results show that 1 dB bandwidth of the transition ranges from 61 to 117 GHz. For the purpose of verification,two transitions in back-to-back connection are measured. The results show that transmission loss is only about 0.9-1.7 dB. This transition is used to interface integrated circuits to waveguide components. The characteristic of the LNA module is measured after assembly. It exhibits a broad bandwidth of 75 to 110 GHz,and has a small signal gain above 21 dB. The noise figure is lower than 5.2 dB throughout the entire W-band (below 3 dB from 89 to 95 GHz) at room temperature. The proposed LNA module exhibits potential for millimeter wave applications due to its high small signal gain,low noise,and low DC power consumption.

On-wafer S-parameter de-embedding techniques from 0.1 to 110 GHz are researched. The solving results of thru-reflect-line (TRL) and line-reflect-match (LRM) de-embedding algorithms, when the input and output ports are asymmetric, are given. The de-embedding standards of TRL and LRM are designed on an InP substrate. The validity of the de-embedding results is demonstrated through two passive components, and the accuracy of TRL and LRM de-embedding techniques is compared from 0.1 to 110 GHz. By utilizing an LRM technique in 0.1–40 GHz and a TRL technique in 75–110 GHz, the intrinsic S-parameters of active device HBT in two frequency bands are obtained, and comparisons of the extracted small-signal current gain and the unilateral power gain before and after de-embedding are presented. The whole S-parameters of actual DUT from 0.1 to 110 GHz can be obtained by interpolation.

A W-band frequency doubler MMIC is designed and fabricated using 1-μm InP DHBT technology. Active balun is employed to transform the single-ended signal into differential output. Push—push configuration loaded with harmonic resonant network is utilized to acquire the second harmonic frequency. A multi-stage differential structure improves the conversion gain and suppresses the fundamental frequency. The MMIC occupies an area of 0.55 × 0.5 mm2 with 18 DHBTs integrated. Measurements show that the output power is above 5.8 dBm with the suppression of fundamental frequency below −16 dBc and the conversion gain above 4.7 dB over 75–80 GHz.