Based on the coupled power theory. the characteristics of optical power and inter-core crosstalk (ICXT) were studied in real multi-core fibers (MCF) with multi-core excitation. According to the simplified coupled power equation of 7-core fiber. the analytical expressions of optical signal power and ICXT in each fiber core were deduced under three multi-core excitation conditions. https://8tenparters.shop/product-category/chainsaw-bars/