Learn More
—The tradeoff of spectral efficiency (b/s/Hz) versus energy per information bit is the key measure of channel capacity in the wideband power-limited regime. This paper finds the fundamental bandwidth–power tradeoff of a general class of channels in the wideband regime characterized by low, but nonzero, spectral efficiency and energy per bit close to the(More)
This paper investigates the maximal channel coding rate achievable at a given blocklength and error probability. For general classes of channels new achievability and converse bounds are given, which are tighter than existing bounds for wide ranges of parameters of interest, and lead to tight approximations of the maximal achievable rate for blocklengths n(More)
This paper deals with arbitrarily distributed finite-power input signals observed through an additive Gaussian noise channel. It shows a new formula that connects the input-output mutual information and the minimum mean-square error (MMSE) achievable by optimal estimation of the input given the output. That is, the derivative of the mutual information(More)
Abrlracr-A h u l a for the cppecity et arbitrary sbgle-wer chrurwla without feedback (mot neccgdueily W i u m " stable, stationary, etc.) is proved. Capacity ie shown to e i p l the supremum, over all input processts, & the input-outpat inf-iqjknda QBnd as the llnainl ia praabiutJr d the normalized information density. The key to thir zbllljt is a ntw a " c(More)
—Performance analysis of the minimum-mean-square-error (MMSE) linear multiuser detector is considered in an environment of nonorthogonal signaling and additive white Gaussian noise. In particular, the behavior of the multiple-access interference (MAI) at the output of the MMSE detector is examined under various asymptotic conditions, including: large(More)
In code-division multiple-access systems, simultaneous multiuser accessing of a common channel is made possible by assigning a signature waveform to each user. Knowledge of these waveforms enables the receiver to demodulate the data streams of each user, upon observation of the sum of the transmitted signals, perturbed by additive noise. Under the(More)
Given a channel and an input process we study the minimum randomness of those input processes whose output statistics approximate the original output statistics with arbitrary accuracy. We introduce the notion of resolva-bility of a channel, defined as the number of random bits required per channel use in order to generate an input that achieves arbitrarily(More)
Consider the following simple communication channel model: an error-free bit pipe leading to a buffer modeled by a single-server queue whose " packets " or " customers " are single bits. If the service rate is p bits/sec, common wisdom would indicate that the Shannon capacity of this communication link is p bits/sec. As we show in this paper, that intuition(More)