Unlike consumer electronics, transfusing the advanced wireless technology into medical equipment has not been rapidly developed. For wireless medical applications, lossless connection and noninvasive transmission are important factors. Moreover, in medical imaging applications such as 4D ultrasound imaging, high-information-rate transmission with a real-time display are demanded. To support the high-definition video format, a data-rate as high as 500Mb/s is desirable for raw data transmission. The mm-Wave transceiver [1] or the MB-OFDM transceiver [2] can provide high data-rate, but high power consumption and high transmission power are shortcomings for medical applications.

9.2 A 13.3mW 500Mb/s IR-UWB transceiver with link-margin enhancement technique for meter-range communications

An energy-efficient crystal-less double-FSK transceiver for wireless body-area-network (WBAN) sensor nodes is implemented in 0.18-μm CMOS technology with a 1-V supply. The injection-locking digitally controlled oscillator (IL-DCO) replaces the crystal oscillator (XO), which leads to significantly reduce the energy consumption and system cost. With the proposed calibration method using an injection-locking detector (IL-detector), the frequency drift of DCO can be calibrated within 100-kHz accuracy over 100° temperature variation. For the full satisfaction to the WBAN requirements, such as wide range of quality of service in terms of data rate, bit error rate, and network coexistence, we adopt a scalable double-FSK modulation scheme with divider-based transmitter by a power-efficient switching modulator. As a result, the fabricated crystal-less double-FSK WBAN compatible sensor node transceiver consumes 1 and 2 mW in calibrating and transmitting modes, respectively, at a data rate of up to 10 Mb/s, providing an 80 MHz reference source with 100-kHz accuracy by auto-calibrated DCO.

A Low-Energy Crystal-Less Double-FSK Sensor Node Transceiver for Wireless Body-Area Network

A frequency-agile FM-UWB transceiver (Tx/Rx) with full on-chip calibration aimed at low data rate autonomous wireless sensing applications is described The subcarrier VCO, 3-phase CCO, and frequency-tripling PA in the transmit path produce a wideband, double-FM output at ${-}$ 101 dBm-pk (FCC compliant) A tunable LNA, envelope detector, limiter, and FSK demodulator comprise the receiver Digitally programmable matching networks at the PA output and LNA input facilitate independent tuning of Tx and Rx across the 3–5 GHz band An on-chip SAR-FLL controlling 5 DACs (3 I-DACs and 2 C-DACs) performs a full Tx/Rx calibration in less than 2 ms Designed for continuous operation at 100 kb/s, measured Rx sensitivity is ${-}$ 805 dBm (10 $^{-3}$ BER), and average Tx/Rx energy efficiency is 6 nJ/bit Total dissipation for the 09 mm $^{2}$ IC implemented in 90 nm RF-CMOS is 630 µW in Tx and 580 µW in Rx mode from a 1 V supply

A Fully Integrated Wideband FM Transceiver for Low Data Rate Autonomous Systems

This paper presents a frequency modulated ultra-wideband (FM-UWB) transceiver system with RF submodules gated by a data-driven control signal. With the control signal, intermittent operation of key building blocks such as a VCO in the transmitter and a wideband FM demodulator in the receiver is realized. To enable an effective dynamic power control, the transmitter generates higher subcarrier frequency and modulation index than conventional FM-UWB transmitters by utilizing an 8-modulo fractional-N PLL in which a triangular waveform is generated by a relaxation VCO. In the receiver, an envelope detector monitors the presence of incoming signal and enables the data-edge-triggered power control for a wideband FM demodulator and other blocks. A prototype 3.5-4.1 GHz FM-UWB transceiver for on-chip wireline testing is implemented in 0.18-μm CMOS. Experimental results show that the proposed gated FM-UWB system successfully demodulates the FSK information, achieving nearly 53% power saving with the data-driven power control enabled.

A Gated FM-UWB System With Data-Driven Front-End Power Control

A low-power regenerative frequency-modulated ultra-wideband (FM-UWB) receiver with wideband signal reception and linear FM-AM conversion is implemented in 65-nm CMOS for short-range communication systems. Different from the conventional regenerative FM-UWB receiver having the narrowband low-noise amplifier (LNA), the proposed receiver employs a wideband LNA and dual bandpass filters (BPFs) to improve the robustness against narrowband interference and frequency shift-keying demodulation with a relaxed Q requirement of the BPF. A 3.5-4-GHz FM-UWB receiver consisting of a stacked LNA, dual BPFs, two envelop detectors, and a subtractor successfully performs FM demodulation through wireless transmission from a 100-kb/s FM-UWB transmitter, consuming the total power of 3.8 mW.

A 3.8-mW 3.5–4-GHz Regenerative FM-UWB Receiver With Enhanced Linearity by Utilizing a Wideband LNA and Dual Bandpass Filters

This paper describes the architecture and circuit design of a low data rate FM-UWB transmitter. A Δ-Σ fractional-N PLL with a multi-phase relaxation oscillator is designed to enable sub-carrier modulation with reduced quantization noise. The triangular waveform output of the relaxation oscillator directly modulates an LC VCO to have the UWB-compliant spectrum. The center frequency of the LC VCO is quasi-continuously tuned by a Δ-Σ DAC based frequency-locked loop with the power consumption of 1.1mW. The 3.43–4.03GHz FM-UWB transmitter implemented in 0.18μm CMOS consumes the total power of 9.6mW.

A low data rate FM-UWB transmitter with-based sub-carrier modulation and quasi-continuous frequency-locked loop

This paper presents a 1Mb/s frequency-modulated ultra-wideband (FM-UWB) transmitter for robust non-invasive short range communications. A 51MHz 8-modulo fractional-N PLL with a relaxation VCO is designed to generate a 2-FSK modulated triangular waveform which directly modulates an RF oscillator. The amplitude of the triangular waveform is controlled digitally, determining the RF bandwidth of the UWB spectrum. The center frequency of the RF oscillator is set by a semi-digital quasi-continuous frequency-locked loop (FLL) which enables digital tuning of the UWB frequency band. A 3.2–4.4GHz prototype FM-UWB transmitter is implemented in 0.18µm CMOS, achieving the data rate higher than the reported by at least four times.

Jinghui Liu

Papers

A Gated FM-UWB System With Data-Driven Front-End Power Control

A low data rate FM-UWB transmitter with-based sub-carrier modulation and quasi-continuous frequency-locked loop

A 1Mb/s 3.2–4.4GHz reconfigurable FM-UWB transmitter in 0.18µm CMOS