Systems and methods for small cell placement using PNM metrics
A communication device is provided for a communication network having a cable plant within an operational vicinity of a macro base station wirelessly transmitting an LTE signal. The communication device includes a processor configured to obtain at least one PNM metric for a cable signal communicated over the cable plant, detect a signature of the LTE signal based on the obtained PNM metric, estimate, based on the detected LTE signature, an existing LTE signal power at a point of leakage in the cable plant, determine a CNR of the cable plant at the point of leakage based on a power of the cable signal and the estimated LTE signal power, and calculate a minimum safe distance from the point of leakage in which a small cell base station may operate without the substantial interference from the LTE signal of the macro base station.
1. A communication device in a communication network having at least one cable plant within an operational vicinity of a macro base station wirelessly transmitting a long term evolution (LTE) signal, the communication device comprising at least one processor configured to:
obtain at least one proactive network maintenance (PNM) metric for a cable signal communicated over the at least one cable plant;
detect, at the communication device, a signature of the LTE signal based on the obtained PNM metric;
estimate, based on the detected LTE signature, an existing LTE signal power at a point of leakage in the at least one cable plant;
determine a carrier to noise ratio (CNR) of the at least one cable plant at the point of leakage based on a power of the cable signal and the estimated LTE signal power; and
calculate a minimum safe distance from the point of leakage in which a small cell base station operates without substantial interference from the LTE signal of the macro base station.
2. The device of claim 1 , wherein the communication device comprises a cable modem.
3. The device of claim 1 , wherein the communication device comprises a cable modem termination system.
4. The device of claim 1 , wherein the PNM metric comprises one or more of a modulation error ratio measurement, a codeword error rate calculation, a forward error correction calculation, a signal to noise ratio measurement, a full band capture measurement, and an energy detection measurement.
5. The device of claim 1 , wherein the processor is further configured estimate the LTE signal power based on a loss from a drop along the at least one cable plant.
6. The device of claim 5 , wherein the processor is further configured to determine the CNR using a predetermined lower bound value.
7. A method for determining a small cell base station placement in a communication network operating within the vicinity of a macro base station wirelessly transmitting a long term evolution (LTE) signal, the method comprising the steps of:
obtaining one proactive network maintenance (PNM) metric for each of a plurality of cable modems disposed within the coverage area of the small cell base station;
identifying, from the obtained PNM metrics, a selected number of the plurality of cable modems exhibiting an ingress signature of the LTE signal;
mapping respective locations of the identified selected number of cable modems;
determining, from the mapped respective locations, likely ingress points of interference from the LTE signal along a cable plant infrastructure of the communication network; and
calculating a minimum safe operating distance, from at least one of the determined likely ingress points, for the small cell base station.
8. The method of claim 7 , wherein the PNM metric comprises one or more of a modulation error ratio measurement, a codeword error rate calculation, a forward error correction calculation, a signal to noise ratio measurement, a full band capture measurement, and an energy detection measurement.
9. The method of claim 7 , wherein a number of the plurality of cable modems is greater than the selected number of cable modems exhibiting the ingress signature.
10. The method of claim 7 , wherein the step of determining further comprises generating a propagation model of the small cell base station.
11. The method of claim 10 , further comprising a step of prioritizing the likely ingress points according to the mapped respective locations and the propagation model.
12. The method of claim 11 , wherein the step of prioritizing is based on the respective costs of mitigating the likely ingress points.
13. The method of claim 11 , wherein the step of prioritizing is based on the respective severity of the detected interference at the likely ingress points.
14. The method of claim 11 , wherein the step of prioritizing includes solution to avoid at least one ingressing LTE signal band.
15. The method of claim 7 , further comprising a step of calculating a received LTE signal power, P LTE _ Rx , according to the equation:
P LTE _ Rx =20 log(λ)−20 log(4π D )+ P Tx +G Tx +G Leak −OPL
where P Tx represents a transmit power of the small cell base station, G Tx represents a transmitted antenna gain of the small cell base station, G Leak represents an antenna gain at the point of leakage, D represents the distance of the small cell base station from the point of leakage, OPL represents an outdoor penetration loss, and λ represents a wavelength of the LTE signal.