A Shared Binary Intensity-Search Architecture for Multi-Sensor ADC-Less Sensing with Two-Peak Telemetry

This paper presents a multi-sensor Binary Intensity-Search Measurement System (BRMS-M) that extends the binary-search, ADC-less sensing principle to N independent two-part sensors—laser, optical, and ultrasonic—each comprising a transmitter (Tx_i) and a receiver (Rx_i). Rather than replicating a measurement path per sensor, all N sensor pairs share a single binary-weighted resistor array that sets transmitter drive intensity, and a single central controller that performs the binary search. Each sensor pair is addressed by a shared selection signal (Sel_i), simultaneously activating its transmitter and enabling its receiver while isolating all other pairs. Measurement proceeds through an intensity-domain binary search: rather than comparing a resistance value against a threshold, the controller sweeps drive intensity from MSB to LSB and reads the receiver’s binary detection output directly, exploiting the sensor’s own detection threshold in place of a dedicated analog comparator. This confines the design to sensors with a monotonic intensity-to-detection response, qualified on the ground prior to flight. Each converged code is telemetered to the ground receiver once per hourly cycle, using a two-peak, pulse-interval encoding inspired by aircraft IFF (Identify Friend or Foe) systems, rather than a per-bit event-driven scheme. This architecture reduces N per-channel measurement paths to a single shared array and controller, positioning it as a scalable, low-power multi-sensor telemetry method suitable for distributed sensing on tethered platforms such as research balloons.