A CMOS baseband‐active‐feedback receiver frontend with passive voltage‐commutating mixers is proposed. The active feedback baseband enables in‐band signal amplification and out‐of‐band blocker interference suppression by constructing the RF bandpass filter and BB lowpass filter, simultaneously. The voltage‐commutating mixers embedded in current mirrors significantly reduce the power requirement for the LO generator. The stacked n/pMOS structure is commonly adopted to further improve power efficiency. The receiver frontend is designed in a standard 65 nm CMOS process. Simulation results display an NF of 3.4 dB and a maximum gain of 32 dB from 1 to 5 GHz LO frequency range. The obtained in‐band and out‐of‐band IIP3 are −12 dBm and 9 dBm, respectively. The receiver frontend core only consumes 22 mW at 1 GHz LO frequency and occupies the area of 645 × 543 μm2, which is suitable for the low‐power application of handheld terminals.

Cancer metastasis is the main cause of cancer‐related death. Early detection of tumor cell in peripheral blood is of great significant to early diagnosis and effective treatment of cancer. Over the past two decades, microfluidic technologies have been demonstrated to have great potential for isolating and detecting tumor cell from blood. The present paper reviews microfluidic techniques for tumor cell detection based on various physical principles. The specific methods are categorized into active and passive methods depending on whether extra force field is applied. Working principles of the two methods are explained in detail, including microfluidics combined with optical tweezer, electric field, magnetic field, acoustophoresis, and without extra fields for tumor cell detection. Typical experiments and the results are reviewed. Based on these, research characteristics of the two methods are analyzed.

A spread spectrum technique and apparatus for reducing electromagnetic interference (EMI) in class D amplifier are introduced. The technique utilizes very simple hardware, where the switching frequency of a class D amplifier is dynamically varied from 1 to 1.22MHz. This is achieved by changing the charging current of an oscillator in a random fashion, through 6 switches that are controlled by 6 random digital signals. Compared to fixed frequency operation, the spectrum of a switching signal was greatly flattened and a reduction of 6dB in the EMI without efficiency and performance degradations was obtained.

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The long-period fiber grating was functionalized with metal–organic framework nanomaterial ZIF-8 for sensitive acetone vapor sensing with large dynamic range and fast response.