## 5 Joint Optimization of FeICIC Parameters and Base-Station Density
### Joint Optimization of Pico CRE Bias and Power Reduction Factor
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Substituting Equations (12) and (13) into Equation (11), and further substituting Equation (11) into Equation (11), we can obtain the closed-form expression of the average achievable downlink rate of a typical UE \(l\) as Equation (9). ## References

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