A Highly Reliable, 5.8 GHz DSRC Wake-Up Receiver with an Intelligent Digital Controller for an ETC System

Abstract

In this article, a highly reliable radio frequency (RF) wake-up receiver (WuRx) is presented for electronic toll collection (ETC) applications. An intelligent digital controller (IDC) is proposed as the final stage for improving WuRx reliability and replacing complex analog blocks. With IDC, high reliability and accuracy are achieved by sensing and ensuring the successive, configurable number of wake-up signal cycles before enabling power-hungry RF transceiver. The IDC and range communication (RC) oscillator current consumption is reduced by a presented self-hibernation technique during the non-wake-up period. For accommodating wake-up signal frequency variation and enhancing WuRx accuracy, a digital hysteresis is incorporated. To avoid uncertain conditions during poor and false wake-up, a watch-dog timer for IDC self-recovery is integrated. During wake-up, the digital controller consumes 34.62 nW power and draws 38.47 nA current from a 0.9 V supply. In self-hibernation mode, its current reduces to 9.7 nA. It is fully synthesizable and needs 809 gates for its implementation in a 130 nm CMOS process with a 94 × 82 µm2 area. The WuRx measured power consumption is 2.48 µW, has −46 dBm sensitivity, and a 0.484 mm² chip area.

A Highly Accurate, Polynomial-Based Digital Temperature Compensation for Piezoresistive Pressure Sensor in 180 nm CMOS Technology

“…Since, the pressure and temperature signals have very low frequencies of a few kHz, therefore, a low speed, high resolution SD-ADC is used for precise digitization of analog signals. The digital processing is more robust and reliable compared to analog processing [ 20 , 21 ]. Also, digital compensation processing is much easier and simpler than in analog techniques.…”

A Highly Accurate, Polynomial-Based Digital Temperature Compensation for Piezoresistive Pressure Sensor in 180 nm CMOS Technology

“…Since, the pressure and temperature signals have very low frequencies of a few kHz, therefore, a low speed, high resolution SD-ADC is used for precise digitization of analog signals. The digital processing is more robust and reliable compared to analog processing [ 20 , 21 ]. Also, digital compensation processing is much easier and simpler than in analog techniques.…”

A Low-Power 12-Bit 20 MS/s Asynchronously Controlled SAR ADC for WAVE ITS Sensor Based Applications

“…2021, 21, x FOR PEER REVIEW 2 of 15 Figure 1 plots the top block diagram of highly integrated 5.8 GHz DSRC transceiver system. It satisfies the aforementioned requirements without any externally connected block like low-noise amplifier (LNA) and external power amplifier (PA) [3]. The main building blocks consists of a matching network (M.N), single pole double throw (SPDT) switch, an inductively generated low-noise amplifier (LNA) to amplify the input signal, a mixer (MIXER), a 12-bit ADC, a 12-bit DAC, a received signal strength indicator (RSSI), a variable gain amplifier (VGA) with a low pass filter (LPF) and power amplifier (PA) [4].…”

Low-Power GPS-Disciplined Oscillator Module for Distributed Wireless Sensor Nodes

“…works require low power usage and may accomplish this via wake-up receivers/oscillators (cf. [15,16]); however, such systems generally do not require that the distributed sensors remain in phase coherence. In cases where this is required-such as the geoPebble system-a GPSDO such as we developed is needed.…”

A Highly Accurate, Polynomial-Based Digital Temperature Compensation for Piezoresistive Pressure Sensor in 180 nm CMOS Technology

“…Since, the pressure and temperature signals have very low frequencies of a few kHz, therefore, a low speed, high resolution SD-ADC is used for precise digitization of analog signals. The digital processing is more robust and reliable compared to analog processing [ 20 , 21 ]. Also, digital compensation processing is much easier and simpler than in analog techniques.…”

A Low-Power 12-Bit 20 MS/s Asynchronously Controlled SAR ADC for WAVE ITS Sensor Based Applications

“…2021, 21, x FOR PEER REVIEW 2 of 15 Figure 1 plots the top block diagram of highly integrated 5.8 GHz DSRC transceiver system. It satisfies the aforementioned requirements without any externally connected block like low-noise amplifier (LNA) and external power amplifier (PA) [3]. The main building blocks consists of a matching network (M.N), single pole double throw (SPDT) switch, an inductively generated low-noise amplifier (LNA) to amplify the input signal, a mixer (MIXER), a 12-bit ADC, a 12-bit DAC, a received signal strength indicator (RSSI), a variable gain amplifier (VGA) with a low pass filter (LPF) and power amplifier (PA) [4].…”

Low-Power GPS-Disciplined Oscillator Module for Distributed Wireless Sensor Nodes

“…works require low power usage and may accomplish this via wake-up receivers/oscillators (cf. [15,16]); however, such systems generally do not require that the distributed sensors remain in phase coherence. In cases where this is required-such as the geoPebble system-a GPSDO such as we developed is needed.…”

A Highly Accurate, Polynomial-Based Digital Temperature Compensation for Piezoresistive Pressure Sensor in 180 nm CMOS Technology

“…Since, the pressure and temperature signals have very low frequencies of a few kHz, therefore, a low speed, high resolution SD-ADC is used for precise digitization of analog signals. The digital processing is more robust and reliable compared to analog processing [ 20 , 21 ]. Also, digital compensation processing is much easier and simpler than in analog techniques.…”

A Low-Power 12-Bit 20 MS/s Asynchronously Controlled SAR ADC for WAVE ITS Sensor Based Applications

“…2021, 21, x FOR PEER REVIEW 2 of 15 Figure 1 plots the top block diagram of highly integrated 5.8 GHz DSRC transceiver system. It satisfies the aforementioned requirements without any externally connected block like low-noise amplifier (LNA) and external power amplifier (PA) [3]. The main building blocks consists of a matching network (M.N), single pole double throw (SPDT) switch, an inductively generated low-noise amplifier (LNA) to amplify the input signal, a mixer (MIXER), a 12-bit ADC, a 12-bit DAC, a received signal strength indicator (RSSI), a variable gain amplifier (VGA) with a low pass filter (LPF) and power amplifier (PA) [4].…”

Low-Power GPS-Disciplined Oscillator Module for Distributed Wireless Sensor Nodes

“…works require low power usage and may accomplish this via wake-up receivers/oscillators (cf. [15,16]); however, such systems generally do not require that the distributed sensors remain in phase coherence. In cases where this is required-such as the geoPebble system-a GPSDO such as we developed is needed.…”