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This paper discusses some challenges in the design of millimeter-wave (mmwave) circuits and systems for 5th generation (5G) wireless systems in CMOS process. The properties of some passive and active devices such as inductors, capacitors, transmission lines, transformers and transistors in mm-wave frequency band are discussed. Self-healing technique dealing with PVT variation, resonant mode switching technique to enhance frequency tuning range of voltage controlled oscillator (VCO) and dual mode technique for power amplifier (PA) efficiency enhancement are introduced. At last, A fully-integrated 60 GHz 5 Gb/s QPSK transceiver with the transmit/receive (T/R) switch in 65nm CMOS process is introduced. The measured error vector magnitude (EVM) of the TX is -21.9 dB while the bit error rate (BER) of the RX with a -52 dBm sine-wave input is below 8e-7 when transmitting/receiving 5 Gb/s data. The transceiver is powered by 1.0 V and 1.2 V supply (except the phase-frequency detector and charge-pump in the frequency synthesizer which are powered by 2.5 V supply) and consumes 135 mW in TX mode and 176 mW in RX mode.

Applying metrics to software is a way to measure and improve software quality. Many metrics apply to software implementations (code), so they cannot be used early in the life cycle. We survey ten modularity and structural complexity metrics applicable to software designs, and summarize the results of empirical validation studies when they are available. We present a database schema from which most of these metrics can be computed. Aspects of each metric require further study and refinement. However, using some of them during design may still be beneficial.

To optimize the use of distributed energy, this work builds a combined cooling heating and power system (CCHP) driven by distributed energy, including three subsystems: the electricity subsystem, CCHP subsystem, and ground source heat pump (GSHP) subsystem. Then, energy, economic and environmental performance indicators are constructed using a natural gas‐driven CCHP system (NG CCHP) as the frame of reference. Thirdly, three system operation modes are put forward, including following the thermal load (FTL) mode, following the electric load (FEL) mode, and electric load combine thermal load (ECT) mode. In the meantime, three kinds of system operation modes are proposed, including optimization of energy rate (ER), total operation cost (TOC), and carbon dioxide emission reduction (CER). Finally, Shanghai World Expo is analyzed as a simulation object. The results show that the optimal target operation strategy can balance the results of different optimization by increasing the partial load rate of the gas‐steam combined cycle system and reducing the pumping ratio of the steam turbine. Compared with the NG CCHP system, the new CCHP system performs better. The sensitivity analysis shows, as the coefficient of performance of the chiller increases and the price of NG decreases, the performance of the new CCHP system will become better. A combined cooling, heating, and power system with multiple distributed energy sources is proposed, and the system is optimized by exploiting the specificity of ground source heat pumps, photovoltaics, and wind energy. Three different operating modes are compared to obtain a more efficient operating mode.