  The problem of decentralized detection in a sensor network subjected to a
total average power constraint and all nodes sharing a common bandwidth is
investigated. The bandwidth constraint is taken into account by assuming
non-orthogonal communication between sensors and the data fusion center via
direct-sequence code-division multiple-access (DS-CDMA). In the case of large
sensor systems and random spreading, the asymptotic decentralized detection
performance is derived assuming independent and identically distributed (iid)
sensor observations via random matrix theory. The results show that, even under
both power and bandwidth constraints, it is better to combine many not-so-good
local decisions rather than relying on one (or a few) very-good local
decisions.
