The C/I calculation in UL is calculated so that C(j,k) is the received power from the UEj,k at the j-th BS.
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| body | $C(j,k)={{P}_{t}}(j,k)\times effective\_pathloss(U{{E}_{j,k}},B{{S}_{j}})$ |
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(Eq. 54)where Pt is the transmit power of the UE in dBm (see UL Power control below) and effective_pathloss is defined as in Section 7.6.1..
The total interference to a UL cellular system is derived from
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| body | I(j,k)={{I}_{i\text{nter}}}(j,k)+{{I}_{ext}}(j,k)+N |
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(Eq. 55)where
- Iinter is the interference coming from UEs of the same system but from adjacent cells, i.e. the inter-system interference from other cells. Since a fully orthogonal system is assumed, only UEs which transmit in the same frequency subcarriers will introduce interference to each other, hence only UEs in other cells with the same k index are considered;
- Iext(j,k) is the interference from external interfering system(s) in adjacent channel;
- N is the noise floor.
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| body | ${{I}_{\text{inter}}}(j,k)=\sum\limits_{l=1,l\ne j}^{{{N}_{cell}}}{{{P}_{t}}(l,k)\times pathloss(U{{E}_{l,k}},B{{S}_{j}})}$ |
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(Eq. 56)
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| body | ${{I}_{\text{ext}}}(j)=\sum\limits_{m=1}^{N}{iRS{{S}_{unwanted}}(IL{{T}_{m}},B{{S}_{j}})+ iRS{{S}_{blocking}}}(IL{{T}_{m}},B{{S}_{j}})$ |
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(Eq. 57)Iext(j,k) is the interference to the the victim BSj from N interfering link transmitters (ILT), where
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| body | $iRS{{S}_{unwanted}}(IL{{T}_{m}},B{{S}_{j}})=iRS{{S}_{unwanted}}(\text{over the size of the UE resource blocks})$ |
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(Eq. 58)
for each of the victim BSj’s frequency where the UL information is received. The ILT can be any generic systems or a BS/UEs of a cellular system.
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| body | $iRS{{S}_{blocking}}(IL{{T}_{m}},B{{S}_{j}})=iRS{{S}_{blocking}}(\text{over system bandwidth})\times \frac{{{\text{N}}_{\text{RB}}}}{\text{M}}$ |
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(Eq. 59)at the victim system frequency. Where NRB is the number of RBs (i.e. subcarriers) requested per UE, and M is the maximum number of RBs per BS.
Image Added (Eq. 60)
where NoiseFigureBS is the noise figure of a BS.