Table 3 Asymptotic performance in terms of \(\mathcal {E} \left \{ \alpha \right \}\) and \(\mathcal {E} \left \{ \beta \right \}\)
From: Distributed estimation in wireless sensor networks with semi-orthogonal MAC
Type of MAC | \(\mathcal {E} \left \{ \alpha \right \}\) | \(\mathcal {E} \left \{ \beta \right \}\) | Number of orthogonal channels, N | Required feedback |
|---|---|---|---|---|
Coherent | 0.78 K | 0.78 K | 1 | Exact channel phase |
Orthogonal | 1 | K | K | None |
Hybrid (N=4) | 0.20 K | 0.78 K | 4 | Exact channel phase |
Semi-orthogonal, fixed (N=4) | 1 | 8 | 4 | None |
Semi-orthogonal, adaptive (N=4) | 0.16 K | 0.78 K | 4 | log2N bits |