User's Guide

12 A c l a r a R F E l e c t r i c I - 2 1 0 + c U s e r G u i d e
Figure 4.1 shows that a field of invisible RF energy is pushed outward from the RF
transmitter located inside the meter canopy. Due to antenna directivity, more
energy will propagate out the face of the meter than the back of the meter. The
energy is directed primarily in the horizontal plane at the same elevation as the
meter, but some energy is directed a few degrees above and below the horizontal.
Figure 4.1 RF propagation concept
Ideally there is line of sight between the meter and the DCU. However, there are
quite often building materials, foliage, vehicles, terrain, and/or the curvature of the
Earth in the way. The RF will transmit through many building materials, be
absorbed by some, and bounce off others. If a sufficiently strong, vertically
polarized signal reaches the receiver, the message will be received. This is true of
RF transmissions from the meter to the DCU, and from the DCU to the meter.
LP Channel Capacity
4 channels
Notes: The storage duration varies as a function of the way LP data collection is defined.
Refer to the Meter User Guide, Chapter 5, Section R
2
for more information on LP storage
duration.
The choice of Interval data transmission rates will have a profound impact on system
bandwidth utilization when large quantities of meters are deployed. The baseline system will
be designed to handle 4 channels of 15-minute interval data transmitted every 15 minutes.
Configurations which increase the number of channels, decrease the interval size and
transmission rate, or both, can increase the bandwidth requirements for the system beyond its
baseline capability. Such configurations must be limited to be a small percentage of the
overall population, or the infrastructure hardware capacity must be increased above baseline
levels, in order to deliver large amounts of fine resolution LP data.
Table 4.1 Product Specifications
Specification Description