A 400 MHz Wireless Neural Signal Processing IC With 625 $\times$ On-Chip Data Reduction and Reconfigurable BFSK/QPSK Transmitter Based on Sequential Injection Locking

IEEE Trans Biomed Circuits Syst. 2017 Jun;11(3):547-557. doi: 10.1109/TBCAS.2017.2650200. Epub 2017 May 19.

Abstract

An 8-channel wireless neural signal processing IC, which can perform real-time spike detection, alignment, and feature extraction, and wireless data transmission is proposed. A reconfigurable BFSK/QPSK transmitter (TX) at MICS/MedRadio band is incorporated to support different data rate requirement. By using an Exponential Component-Polynomial Component (EC-PC) spike processing unit with an incremental principal component analysis (IPCA) engine, the detection of neural spikes with poor SNR is possible while achieving 625× data reduction. For the TX, a dual-channel at 401 MHz and 403.8 MHz are supported by applying sequential injection locked techniques while attaining phase noise of -102 dBc/Hz at 100 kHz offset. From the measurement, error vector magnitude (EVM) of 4.60%/9.55% with power amplifier (PA) output power of -15 dBm is achieved for the QPSK at 8 Mbps and the BFSK at 12.5 kbps. Fabricated in 65 nm CMOS with an active area of 1 mm 2, the design consumes a total current of 5 ∼ 5.6 mA with a maximum energy efficiency of 0.7 nJ/b.

MeSH terms

  • Action Potentials*
  • Algorithms
  • Amplifiers, Electronic
  • Electric Power Supplies
  • Equipment Design
  • Humans
  • Neurons / physiology*
  • Signal Processing, Computer-Assisted*
  • Wireless Technology*