I think need full matrix cut to small matrices with size 16*16 elements. Every small matrix have self controller which scan sensors and perform calculation for every sensor to unify output values. That need for following reasons: 1. Don't need to use hight speed ADC for scan sensors, because every controller scan small matrix. At the same time scan more sensors (one in every small matrix). Unify results send to main controller in digital format. 2. Distortion caused tag capacity, inductivity and other minimized, because use short wires for every small matrix. 3 Every controller stored calibrate coefficients in built-in flash memory for each sensor. 4. In current time exist small size controllers. For example PIC16LF1512 has 17 line ADC with 10 bit resolution have size only 4*4 mm. and price <1$ All drowing and full description I will send later.