ABSTRACT
With the advent and popularity of Smart Grids and advanced meter reading, more and more NB-PLC systems are available on the market. It becomes more difficult for customers to choose the best solution for their application. At the same time, system designers and researchers are developing a new generation of PLC modems. For system verification and benchmark testing, engineers are no longer satisfied with test methods and equipment adopted from other communication industries. For example, a vector signal generator is very popular in mobile phone and wireless tests. You can build a transmitter in it, generate the test signal to investigate the receiver and add noise and attenuation, so that the transmit signal seems to be distorted by a real channel. This method is accurate and flexible. However, it needs exact details of the device under test (DUT). If you want to test several devices of different technologies, you have to build a transmitter for each one. You can also connect the transmitter and receiver with a switchable attenuator; noise can be generated by using a low-cost function generator. Spectrum analysers and oscilloscopes can be used to measure signals and noise at the receiver. If the attenuation can work for both 576directions, a bidirectional communication can be tested. However, usually, the attenuator is flat for wide frequency range, so the performance against frequency-selective attenuation cannot be evaluated. It has low flexibility and also high cost. Alternatively, you can connect the DUT to mains network directly. Although such test results are highly realistic, they suffer from the lack of reproducibility and low flexibility.
