1. RRU & RS Power (PA dependent on pb)
Results
RRU Power (dBm)
47.78 dBm
RS Power (dBm)
15.20 dBm
RS Power Equation ($P_{\text{RS}}$)
LaTeX Notation
$$P_{\text{RS(dBm)}} = P_{\text{RRU(dBm)}} - 10 \cdot \log_{10}(TX_{\text{ports}}) - 10 \cdot \log_{10}(\text{Total Resources}) + 10 \cdot \log_{10}(1 + p_b) - 0.05$$
Where $\text{Total Resources} = 60 \cdot \text{BW}_{\text{MHz}}$ (LTE resource element count approximation for a full OFDM symbol).
Where $\text{Total Resources} = 60 \cdot \text{BW}_{\text{MHz}}$ (LTE resource element count approximation for a full OFDM symbol).
Python Equivalent (with `math` module)
import math
# Define Variables (Example: 60W RRU, 2TX, 15MHz, pb=0)
rru_power_dbm = 47.78
tx_ports = 2
bandwidth_mhz = 15
pb = 0
# Calculated intermediate value
total_resources = 60 * bandwidth_mhz
# RS Power (dBm) calculation
rs_power_dbm = rru_power_dbm - (10 * math.log10(tx_ports)) - (10 * math.log10(total_resources)) + (10 * math.log10(1 + pb)) - 0.05
Excel Lambda Equivalent (RS Power, $P_{\text{RS}}$)
=LAMBDA(RRU_dBm, TX, BW, pb,
RRU_dBm - 10*LOG10(TX) - 10*LOG10(60*BW) + 10*LOG10(1+pb) - 0.05
)
Usage Example: =RS_POWER_CALC(47.78, 2, 15, 0)
2. Real Transmit Power (PA independent)
Calculated Results
Real Transmit Power (W)
59.300 W
Real Transmit Power (dBm)
47.73 dBm
Type A (W)
59.300 W
Type B (W)
39.600 W
Real Transmit Power Equations ($P_{\text{Real}}$)
LaTeX Notation (Type A and Type B)
$$P_{\text{Type A(W)}} = \left(\frac{10^{\frac{P_{\text{RS(dBm)}} + P_A + 10 \cdot \log_{10}(\text{Total Resources})}{10}}}{1000}\right) \cdot TX_{\text{ports}}$$
$$P_{\text{Type B(W)}} = \left(\frac{10^{\frac{P_{\text{RS(dBm)}} + 10 \cdot \log_{10}(C_1 + C_2)}{10}}}{1000}\right) \cdot 2$$
$$P_{\text{Real(W)}} = \max(P_{\text{Type A(W)}}, P_{\text{Type B(W)}})$$
Note: $C_2 = 5 \cdot \text{BW}_{\text{MHz}} \cdot \begin{cases} 10 & \text{if } TX=1 \\ 8 & \text{if } TX \ge 2 \end{cases}$
$$P_{\text{Type B(W)}} = \left(\frac{10^{\frac{P_{\text{RS(dBm)}} + 10 \cdot \log_{10}(C_1 + C_2)}{10}}}{1000}\right) \cdot 2$$
$$P_{\text{Real(W)}} = \max(P_{\text{Type A(W)}}, P_{\text{Type B(W)}})$$
Note: $C_2 = 5 \cdot \text{BW}_{\text{MHz}} \cdot \begin{cases} 10 & \text{if } TX=1 \\ 8 & \text{if } TX \ge 2 \end{cases}$
Python Equivalent (with `math` module)
import math
# Define Variables (Example: Defaults from Calc 2 inputs)
rs_power_dbm = 15.2
tx_ports = 2
bandwidth_mhz = 15
pb = 0
pa = 0
# Calculated intermediate values
total_resources = 60 * bandwidth_mhz
# NOTE: getTypeBC1Factor function must be defined separately for this snippet to run
# For example purposes, we'll manually set C1 based on the function result:
C1 = 1.25 # Corresponds to TX=2, pb=0
C2 = bandwidth_mhz * 5 * (10 if tx_ports == 1 else 8)
# Type A (W)
type_A = (10**((rs_power_dbm + pa + 10 * math.log10(total_resources)) / 10) / 1000) * tx_ports
# Type B (W)
type_B = (10**((rs_power_dbm + 10 * math.log10(C1 + C2)) / 10) / 1000) * 2
# Real Transmit Power (W)
real_power_w = max(type_A, type_B)
Excel Lambda Equivalent (Real Transmit Power, $P_{\text{Real(W)}}$)
=LAMBDA(RS_dBm, TX, BW, pb, PA,
LET(
C1, IF(TX=1, SWITCH(pb, 0, 1, 1, 4/5, 2, 3/5, 3, 2/5), SWITCH(pb, 0, 5/4, 1, 1, 2, 3/4, 3, 1/2)),
C2, BW * 5 * IF(TX=1, 10, 8),
TYPE_A, (10^((RS_dBm + PA + 10*LOG10(60*BW)) / 10) / 1000) * TX,
TYPE_B, (10^((RS_dBm + 10*LOG10(C1 + C2)) / 10) / 1000) * 2,
MAX(TYPE_A, TYPE_B)
)
)
Usage Example: =REAL_POWER_CALC(15.2, 2, 15, 0, 0)