An ultra low power digital receiver architecture for biomedical applications

Abstract

The emerging biomedical applications urge ultra low power consumption and small size transceivers. In this paper traditional modulations schemes have been studied and compared to a novel modulation scheme called Saturated Analog Signal (SAS), which has been developed specifically for these new applications. This new modulation has been combined with a new design for the receiver in 65nm technology and resulted in a digital CMOS receiver with 10 µW power consumption. The receiver achieved a 500 Kb/s data rate, giving it a 20pJ/bit received consumption. This design uses a 1 V power supply while occupying an area of just 0.6 mm 2 and is capable of being fully integrated on single chip solutions for ultra low power biomedical applications such as retinal prosthesis and embedded neural applications.

Ultra‐low‐power wireless transmitter for neural prostheses with modified pulse position modulation

“…The transmitter inherits the flexibility of the modulation, enabling it to dynamically trade power consumption with data rate and range. This modulation increases the bandwidth of the transmitted signal and hence the noise bandwidth but, since the receiver architecture for SAS compensates for noise performance penalty and the overall power consumption and size benefits outweigh this performance loss, the final results show better energy efficiency and smaller implementation size in both the transmit and receive sides [6].…”

“…The choice of modulation scheme and transceiver architecture extensively influences these features. This has led to a significant research effort towards reducing the overall power consumption and area occupied by such devices [1][2][3][4][5][6]. Also, since the energy sources for such devices should also occupy a small area (<25 mm 2 ), the peak power available from such sources is also restricted (<5 mW).…”

“…This Letter demonstrates the possibility of low‐power, low‐complexity transmitters with suitable energy efficiency and data rate for emerging NP by exploiting a modified modulation scheme called saturated amplified signal (SAS) [6]. This modulation is briefly explained in the following Section and is followed by the transmitter circuit design and measurement results from the implementation.…”

A 27.6 µW 315 MHz low-complexity OOK receiver with on-off RF front-end

“…Alternatively, the RF signal is amplified by the RF amplifier and then clipped by a threshold circuit (comparator) to have digital rail level. After the threshold circuit, signal is considered as a digital stream [6]. The digital processing block will use this stream to demodulate baseband signal.…”

“…Recently, many low power receivers have been reported [1,2,3,4,5,6,7,8]. The receivers on [1,2] and [4] are down-conversion receivers with on-chip local oscillators and mixers.…”