Table 1 Key system parameters in the basic CR system
From: Channel direction information probing for multi-antenna cognitive radio system
λ u | the channel gain from the PT to the PR |
λ f | the channel gain from the PT to the ST |
λ p | the channel gain from the ST to the PR |
μ 0 | the angle position of SR |
\(\mu /\hat {\mu }\) | the angle/acquired angle position of PR |
\(\pmb {h}/\bar {\pmb {h}}(\mu)\) | the channel vector/the CDI from the PT to the ST |
N | the number of antennas at the ST |
δ μ | the half-range of probing region |
P t /P 0 | the transmit power at the PT/ST |
P f /P f,0 | the received signal power at the ST from the PT under |
probing/no probing | |
ρ | the target SINR at the PR |
σ 2 | the receiver noise power at the PR |
g | the probing gain at the ST |
I 1/I 2 | the interference at the PR led by the 1th/2nd type of |
probing signal | |
Ξ 1/Ξ 2 | the hidden feedback information from the PT to the ST led |
by the 1th/2nd type of probing signal | |
r | the ratio for the CDIsp with the PR |