26 research outputs found
Bit error rate measurement above and below bit rate tracking threshold
Bit error rate is measured by sending a pseudo-random noise (PRN) code test signal simulating digital data through digital equipment to be tested. An incoming signal representing the response of the equipment being tested, together with any added noise, is received and tracked by being compared with a locally generated PRN code. Once the locally generated PRN code matches the incoming signal a tracking lock is obtained. The incoming signal is then integrated and compared bit-by-bit against the locally generated PRN code and differences between bits being compared are counted as bit errors
Yield Decrease of Corn Sown into Italian Ryegrass by Minimum Tillage
The objective of this study was to determine the factor causing yield decrease of corn (Zea mays L.) sown into Italian ryegrass (Lolium multiflorum Lam.) by minimum tillage. 5 plots with 2 replications were made, consisting of the number of harvest times of Italian ryegrass, tillage system, and herbicide application. They were 1CT (Italian ryegrass was harvested once/conventional tillage), 1MT (once/minimum tillage), 1MTH (once/MT/herbicide), 2CT (twice/ CT), and 2MT (twice/MT). 1MT produced lowest corn yield and highest Italian ryegrass litter. This observation suggested that corn yield decrease was attributed to competition with Italian ryegrass regrowth. NAR in 1MT after 5 leaf stage indicated considerable decline in comparison with the others. Relative light intensity was under 5% in 1MT, in which the corn couldn\u27t grow. There was no certain trend between plots in soil property. From these results, it was concluded that shading caused by Italian ryegrass was the main factor of yield decrease of corn in minimum tillage