Bounds on ε-capacity for linear multi-input/multi-output channels with applications to telephone subscriber loop channels

Summary form only given. The authors have extended the bounds on ε-capacity given by W. L. Root (1978) for single-input/single-output channels to multi-input/multi-output channels. This extension uses a result due to L. E. Lerer (1978) on the eigenvalue distribution of a convolutional integral operator with a matrix kernel (impulse response). The results have been used to assess the increase in data rates achieved by designing input signals which exploit the multidimensional nature of the channel, relative to treating each constituent channel in isolation. Numerical results based on a first-order model for telephone subscriber loop channels have indicated that an increase by a factor of 2.5 to 3 times in data rates should be possible by exploiting the multidimensionality of the channel.