Architectures for Particle Filtering - Signal Processing Systems - page 654

Fig. 19 Performance of the resampling mechanism. Four PEs operated with 1,024 particles is
considered. The worst-case weight distribution is assumed

For example, for the particle filter used in the bearings-only tracking application,
one particle contains four data where two are used to represent the position and the
other two are used to represent the velocity of an object being tracked. The size
of the memory should be large enough so that the particles can be buffered before
the designated PE reads them out. Thus the total amount of memory for P =

2and

>

P 2, respectively, is given by

MEM total = 3 M [ DW + V ] , (10)

MEM total = 4 M [ DW + V ] . (11)

Bus complexity between the PE and the CU heavily depends on D , which is the
dimension of the particle filter. In the bearings-only tracking problem, D

= 4. The

number of total bus wires between PEs and CU is given by

N wire = P [ DW + V ] . (12)

Thus when the value D increases, the wires required can be significant. The choice
of P is then depending on wires availability and feasibility for integration. It is
possible that particle transfers are time-multiplexed using a smaller ( D < D )set