  To enable low-power and low-complexity wireless monitoring, an improved
circuit design of Analog Joint Source Channel Coding (AJSCC) is proposed for
wireless sensor nodes. This innovative design is based on Analog Divider Blocks
(ADB) with tunable spacing between AJSCC levels. The ADB controls the switching
between two types of Voltage Controlled Voltage Sources (VCVS). LTSpice
simulations were performed to evaluate the performance of the circuit, and the
power consumption and circuit complexity of this new ADB-based design were
compared with our previous parallel-VCVS design. It is found that this improved
circuit design based on ADB outperforms the design based on parallel VCVS for a
large number of AJSCC levels (>= 16), both in terms of power consumption as
well as circuit complexity, thus enabling persistent and higher
temporal/spatial resolution environmental sensing.
