Low-Power Wireless Transceiver With 67-nW Differential Pulse-Position Modulation Transmitter

Abstract

This article presents a low-power wireless narrowband (NB) transceiver consisting of a 434-MHz NB transmitter (NBTX) and a 434-MHz NB receiver (NBRX) implemented in 0.18 µm CMOS. The NBTX utilizes differential pulse-position modulation (DPPM) to decrease consumed energy per bit (EPB) by up to 67% compared to on-off keying (OOK). The packet error performance of DPPM with a soft-decision decoding scheme is analyzed. According to the results, the packet error ratio (PER) does not deteriorate compared to OOK except at very low signal-to-noise levels. The lowest power consumption of the NBTX is 8.3 µW when DPPM data is transmitted continuously. Utilizing packet-mode transmission, the average power consumption is 67 nW at a data rate of 4.8 kbps. The transmitted data was received with a PER of 0.1% by a receiver placed at a 30-meter distance from the NBTX. With a higher power consumption of 2.5 µW at the same data rate, the estimated line-of-sight (LOS) uplink range is up to 200 meters. The NBRX is a mixer-first uncertain-IF receiver. A temperature-compensated ring oscillator (TCRO) is utilized as a local oscillator. Its measured deviation of frequency is from +0.1% to -1.2% over a temperature range from -40 to +85 • C. The NBRX utilizes Manchester encoding and the sensitivity is -87 to -82 dBm over the temperature range at a data rate of 40 kbps. The NBRX consumes 85 µW.

Foundations of Wireless Information and Power Transfer: Theory, Prototypes, and Experiments

“…Additional power consumption for acquiring CSIT is required for the superimposed OFDM-SMF signal. On the other hand, the noncoherent PPM signal for the integrated receiver demands less than a few mW for information decoding [79]. Overall, the PS receiver can potentially achieve a wider R-E region at the cost of large energy consumption.…”

Outlooks on Transmitter Energy Efficiency and FOM and a −189.7-dBJ/bit ULP DPPM Transmitter

“…In this article, we continue the work of [1] and compare DPPM not only with OOK, but additionally with BPSK, BFSK and pulse-position modulation (PPM). The majority of power in ULP transmitters is consumed by the carrier synthesizer and power amplifier (PA) [3].…”

“…In [1], we discussed the benefits of M-ary modulations. These have the potential to achieve higher transmitter energy efficiency compared to binary modulations due to the reduced active time per bit of high-power transmitter circuits.…”

“…Despite the low EPB, a 30-meter uplink range was achieved in measurements. Thus, [1] showed the potential of M-ary DPPM regarding ULP transmitters and its energy efficiency compared to OOK.…”

“…Here, Q(a, b) is the Marcum-Q function and γ = A 2 /2σ 2 is the SNR in the envelope detector (ED) output. The ED output is ideally Rician [1,Eq. 5] and Rayleigh [1,Eq.…”