Journal: Sensors (Basel, Switzerland)

Article Title: Towards Continuous and Ambulatory Blood Pressure Monitoring: Methods for Efficient Data Acquisition for Pulse Transit Time Estimation

doi: 10.3390/s20247106

Figure Lengend Snippet: A simulated example of encoding and decoding a three-sample packet with a 14-bit single data channel. ( a ) The compression table stored on the MCU ( M = 14 , m = 3 , k = 5 ), which maps the 11 upper bits of the magnitude of residuals to Huffman codes. ( b ) The tree stored on the smartphone for decoding Huffman codes. ( c ) d [ 0 ] is sent in its raw form so that packets are self-contained and can be decoded out of order, d [ 1 ] is encoded because 2 is in the compression table, and d [ 2 ] is transmitted in its raw form because 5 is not in the compression table. ( d ) An illustration of the steps for encoding packets. ( e ) An illustration of the steps for decoding packets. It should be noted that: (1) the two uppermost unused bits are removed by the encoder and replaced by the decoder; and (2) β [ n 1 : n 2 ) denotes values of bits n 1 , n 1 + 1 , … , n 2 − 1 in the bit sequence β .

Article Snippet: Although the first 16 ( 2 4 ) bins are not exactly uniformly distributed, their Huffman codes (computed with MATLAB and provided in ) are all 4-bits long.

Techniques: Sequencing