Biometric System on Cards Pave Way for a No-Contact Checkout Experience

July 22, 2020 by Antonio Anzaldua Jr.

BSoCs show how the design demands in the medical and e-commerce industries are notably shifting as a reaction to COVID-19.

While many grocery and supply services are available through online shopping and curbside drop-off—especially in the midst of the COVID-19 pandemic—there still comes a time when you may find yourself physically at a store. 

Many of these reopening businesses are adhering to sanitizing practices and social distancing to avoid COVID-19 transmission, but one unavoidable point of contact appears at store checkouts. If you are paying by card, you may have to make contact with the keypad, which is not always sanitized. 

STMicroelectronics (ST) and Fingerprint Cards AB (Fingerprints) recently joined forces to develop a biometric payment card solution for secure, contactless payment methods—a newly-important banking characteristic during the pandemic. 



BSoC. Image used courtesy of STMicroelectronics


The two companies are accomplishing this through fingerprint-recognition technology, which includes a biometric system-on-card (BSoC) solution. The collaboration aims to address the market demand for enhanced contactless payment-card security and convenience. 


What is a Biometric System-on-Card (BSoC)?

The concept of BSoC came about in 2014 when Fingerprints launched a touch sensor for an Android smartphone. It featured capacitive touch sensors that offered several advantages, such as high image quality and 256 gray-scale values from every pixel element.

Today, the sensors support software for both Android and embedded systems. The compact sensors are all capable of sustaining millions of repeated fingerprint readings.

In early July, the BSoC integration combines STMicroelectronics’ latest-generation secure-payment technology based on the ST31/STPay chipset and STM32 general-purpose microcontrollers with Fingerprints’ T-shape sensor module to provide a contactless, battery-less secure solution.


BSoC Architecture

What's the basic architecture of BSoCs in general? The entire biometric authentication, including the acquisition of a biometric sample, is performed in the smart card or integrated circuit card (ICC). The BSoC module consists of an on-card biometric sensor, processor, memory, and interface device for communication. 


Biometric system-on-card,

Biometric system-on-card, including the capturing device, is implemented inside the smart card. Image used courtesy of Springer Link


The on-card biometric sensor captures a biometric image/signal. Data is stored in secure memory. During verification, the biometric data is used as a query template that will then be compared with the biometric reference data to generate a comparison score. This comparison score will be compared with the internal predefined security threshold to decide whether the query is from the genuine user or an imposter.

The BSoC module will then update its security status for processing the subsequent transaction requested by the user.


Transcending Biometric Data

The cost and complexity for prototyping BSoC are high since all the components are required to be integrated on the smart card. Most research related to on-card biometric comparison is using off-the-shelf smart cards for prototyping as well as a sensor attached to the PC to capture the biometric samples.


Fingerprints technology is said to minimize false rejections

Fingerprints technology is said to minimize false rejections. Image used courtesy of Fingerprints


The contactless payment card will be the first target under ST and Fingerprints research and development agreement with the intention to extend to other markets such as identification, health, access, and transportation cards. 

This technology can provide strong identity authentication and may open more business opportunities that require a two-factor authentication token.