论文标题
高斯随机多个访问通道的单位能量容量
Capacity per Unit-Energy of Gaussian Random Many-Access Channels
论文作者
论文摘要
我们考虑一个带有随机用户活动的高斯多访问通道，其中用户总数$ \ ell_n $和活动用户的平均数量$ k_n $可能是无限的。对于此频道，我们表征可以根据$ \ ell_n $和$ k_n $可靠地传输每单位能量传输的最大位数。我们表明，如果$ k_n \ log \ ell_n $在$ n $中是sublinear，则每个用户可以实现单位能量的单用户容量。相反，如果$ k_n \ log \ ell_n $是$ n $的超级线，则单位能量的容量为零。我们进一步证明，当所有用户都具有概率的活性时，正交访问方案都是最佳的，可以严格次优。
We consider a Gaussian multiple-access channel with random user activity where the total number of users $\ell_n$ and the average number of active users $k_n$ may be unbounded. For this channel, we characterize the maximum number of bits that can be transmitted reliably per unit-energy in terms of $\ell_n$ and $k_n$. We show that if $k_n\log \ell_n$ is sublinear in $n$, then each user can achieve the single-user capacity per unit-energy. Conversely, if $k_n\log \ell_n$ is superlinear in $n$, then the capacity per unit-energy is zero. We further demonstrate that orthogonal-access schemes, which are optimal when all users are active with probability one, can be strictly suboptimal.
