Laserfiche WebLink
20 <br />AMI Feasibility Report I Client Name: City of Santa Ana <br />There are two primary architectures for fixed network water AMI solutions: star network (point to <br />multipoint) and mesh network. In addition, some vendors have started offering AMI solutions <br />utilizing public cellular network. Figure 6 shows an example of the star network, mesh network and <br />cellular networks. <br />RN I Mesh Network -, 11 intto Multi- � Cellular Network <br />r Point Network <br />AMISystem ( AMI System AM1fl System FIs` , <br />Communication Network �� Communication Network —.,_ -_,) <;-�V public Cellular Network- - <br />1 1 \ <br />1 1 \ <br />Cyk'l <br />1 <br />1 <br />1 V I <br />■ Data Collection Unit <br />O Smart Meter <br />Repeater <br />QTower (Data Collection) <br />Figure 6 AMI Primary Network Architectures <br />5.3.1 Star Network <br />A star network is a point-to-point architecture and is a common type of fixed network AMI system <br />used for electric, gas, and water AMIs in North America, where MTU transmits its data to a <br />centralized hub known as a collector or DCU. A MTU's signal may be forwarded by radio frequency <br />or aggregated onto an IP network to send data to the main collection point. In its simplest form, a <br />star network consists of a number of collectors and AMI HES, which acts as a conduit to transmit <br />data. Once the data are received by a collector, the collector transmits the data back to the AMI <br />HES. <br />The advantage of having a star network in place is that it sets up and expands easily and <br />demonstrates good performance. Non -centralized failure has little impact to the entire network, <br />end-point failure is easy to detect, and the data is easily sent directly to data collectors without <br />being repeated through another device. One disadvantage of having a star network is that if a <br />collector fails, all of the end-points that are assigned to that collector may not be transmitted back <br />to the AMI HES. As a result, it is common practice to provide extra collection hardware to create <br />network redundancy in the event of a component failure. <br />5.3.2 Mesh Network <br />Another common type of fixed network system is the mesh network In a mesh network, smart end <br />points act as repeaters, passing the data to other nearby devices until arriving at a main collector. A <br />25G-138 <br />