System and method for coverage analysis in a wireless network

• US 8,060,102 B2
• Filed: 12/14/2004
• Issued: 11/15/2011
• Est. Priority Date: 12/14/2004
• Status: Active Grant

• Current Assignee: BCE Incorporated
• Original Assignee: BCE Incorporated
• Inventors: Gazzola, James Peter
• Primary Examiner(s): Edouard; Patrick
• Assistant Examiner(s): Huynh; Chuck
• Application Number:
  US11/010,338
• Publication Number:
  US 20060128372A1
• Time in Patent Office: 2,527 Days
• Field of Search: 455/446, 455/423, 455/436, 455/454
• US Class Current: 455/446
• CPC Class Codes: H04W 16/18 Network planning tools

Abstract

The present invention is a system and method for coverage analysis in a wireless network. The invention seeks to evaluate the location and characteristics of a proposed base station in a wireless communication network, prior to the base station being erected. Data is collected from both: a test transmitter of known characteristics, erected at the proposed location for the proposed base station; and from a plurality of wireless channels of the existing network. The data may be collected at a plurality of measurement locations. The collected data is used to model and subsequently evaluate the behaviour of the network in the presence of channels that would be introduced into the network if the new base station were erected. Modeled data may include estimates of signal to noise ratios for various wireless channels for both existing base stations and the proposed base station, at the measurement location. The model data may be displayed on a GUI, depicting modeled signal characteristics in a geographical area surrounding the proposed base station, to estimate overall acceptability of a proposed base station at a proposed location before incurring the cost of installing the base station.

Claims

1. A method for analysing a wireless network with a proposed base station added at a proposed location, the method comprising:

receiving first data representative of a test signal received at a measurement location from a test transmitter at the proposed location, and second data representative of at least one communication signal received at the measurement location from the existing wireless network, wherein the first data comprises a signal strength for the test signal received at the measurement location, wherein the second data comprises a power spectrum density indication for the existing wireless network at the measurement location, and wherein the second data further comprises signal strengths for a plurality of communication signals received at the measurement location, each communication signal corresponding to a respective one of a plurality of communication channels transmitted by one or more existing base stations within the wireless network; and

processing the first and second data to estimate at least one signal characteristic at the measurement location for the wireless network with the proposed base station added;

wherein said processing comprises;

estimating a test signal strength for a signal received at the measurement location from the proposed base station using the signal strength for the test signal;

estimating a power spectrum density at the measurement location for the wireless network with the proposed base station added using the power spectrum density indication for the existing wireless network at the measurement location and an estimate of a total signal strength for a signal received at the measurement location from the proposed base station;

estimating a signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station, the estimate of the signal-to-noise ratio comprising the estimate of the test signal strength for a signal received at the measurement location from the proposed base station divided by the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added; and

estimating a signal-to-noise ratio for each of the plurality of communication channels at the measurement location, each signal-to-noise ratio comprising the signal strength for the respective communication signal received at the measurement location from the corresponding existing base station divided by the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added;

estimating the number of handoff states available to a wireless device at the measurement location within the wireless network with the proposed base station added by counting the number of communication channels at the measurement location transmitted by the proposed base station or one of the existing base stations that have an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

2. The method according to claim 1, wherein the estimating a test signal strength for a signal received at the measurement location from the proposed base station comprises estimating a path loss between the measurement location and the proposed location using the signal strength for the test signal and one or more known characteristics of the test transmitter and estimating the total signal strength for a signal received at the measurement location from the proposed base station using the path loss and one or more known characteristics of the proposed base station.

3. The method according to claim 1, wherein the power spectrum density indication for the existing wireless network at the measurement location comprises a combination of signal strengths for a plurality of signals received at the measurement location from existing base stations within the wireless network.

4. The method according to claim 3, wherein the plurality of signals received at the measurement location from existing base stations within the wireless network comprise a predetermined subset of all signals received at the measurement location from existing base stations within the wireless network, the predetermined subset including signals with the greatest signal strengths received at the measurement location from existing base stations.

5. The method according to claim 1, wherein the plurality of communication signals received at the measurement location comprise a plurality of pilot signals corresponding to respective communication channels transmitted by one or more existing base stations within the wireless network.

6. The method according to claim 1, further comprising determining if at least one of the communication channels at the measurement location transmitted by at least one of the proposed base station and one of the existing base stations has an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

7. The method according to claim 1 further comprising estimating if a wireless device at the measurement location would have an acceptable number of handoff states, wherein an acceptable number of handoff states is between one and an acceptable maximum threshold level of handoff states.

8. The method according to claim 1, wherein the first data comprises data representative of the test signal received at each of a plurality of measurement locations from the test transmitter at the proposed location, and the second data comprises data representative of at least one communication signal received at each of the plurality of measurement locations from the existing wireless network;

and

wherein the processing step comprises processing the first and second data to estimate at least one signal characteristic at each of the plurality of measurement locations for the wireless network with the proposed base station added.

9. The method according to claim 8 further comprising collecting the first and second data at the plurality of measurement locations.

10. The method according to claim 9, wherein the collecting the first data comprises measuring a signal strength for the test signal received at each of the plurality of measurement locations from the test transmitter at the proposed location;

and the collecting the second data comprises measuring a signal strength for the at least one communication signal received at each of the plurality of measurement locations from the existing wireless network and measuring a power spectrum density indication for the existing wireless network at each of the plurality of measurement locations.

11. The method according to claim 9, wherein the first and second data are collected at respective first and second frequencies, the second frequency being a used frequency within the existing wireless network and the first frequency being an unused frequency within the existing wireless network.

12. The method according to claim 1, wherein the at least one signal characteristic comprises at least one of:

a power spectrum density at the measurement location for the wireless network with the proposed base station added;

a signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station within the wireless network with the proposed base station added;

a signal-to-noise ratio for a communication channel at the measurement location transmitted by an existing base station within the wireless network with the proposed base station added;

an indication of the number of handoff states available at the measurement location within the wireless network with the proposed base station added; and

an indication of whether a wireless device at the measurement location within the wireless network with the proposed base station added would have an acceptable number of handoff states.

13. The method according to claim 1, further comprising transmitting graphical user interface data to a display apparatus, the graphical user interface data comprising geographical information depicting at least a portion of the wireless network and the estimate of at least one signal characteristic to be delineated local to the measurement location within the geographical information.

14. The method according to claim 1, wherein the measurement location comprises at least one of a specific geographical location and a limited geographical area grouped together.

15. An apparatus for analysing a wireless network with a proposed base station added at a proposed location, the apparatus comprising:

an input device operable to receive first and second data, the first data comprising a signal strength for a test signal received at the measurement location from a test transmitter at the proposed location and the second data comprising a power spectrum density indication at the measurement location for the existing wireless network, wherein the second data further comprises existing base station data comprising signal strengths for a plurality of communication signals received at the measurement location each communication signal corresponding to a respective one of a plurality of communication channels transmitted by one or more existing base stations within the wireless network; and

a processing apparatus, coupled to the input device, operable to estimate a power spectrum density at the measurement location for the wireless network with the proposed base station added using the first and second data wherein the processing apparatus is further operable to;

estimate a signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station using the first data and the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added; and

estimate a signal-to-noise ratio for each of the plurality of communication channels at the measurement location transmitted by one of the existing base stations using the existing base station data and the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added;

estimate the number of handoff states available to a wireless device at the measurement location within the wireless network with the proposed base station added by counting the number of communication channels at the measurement location transmitted by the proposed base station or one of the existing base stations that have an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

16. The apparatus according to claim 15, wherein the power spectrum density indication for the existing wireless network at the measurement location comprises a combination of signal strengths for a plurality of signals received at the measurement location from existing base stations within the wireless network.

17. The apparatus according to claim 15, wherein the second data further comprises existing base station data comprising a signal strength for at least one communication signal received at the measurement location from at least one existing base station within the wireless network;

and wherein the processing apparatus is further operable to estimate a signal-to-noise ratio for a communication channel at the measurement location transmitted by the existing base station using the existing base station data and the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added.

18. The apparatus according to claim 15, wherein the processing apparatus is further operable to determine if at least one of the communication channels at the measurement location transmitted by at least one of the proposed base station and one of the existing base stations has an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

19. The apparatus according to claim 15, wherein the processing apparatus is further operable to estimate if a wireless device at the measurement location would have an acceptable number of handoff states, wherein an acceptable number of handoff states is between one and an acceptable maximum threshold level of handoff states.

20. The apparatus according to claim 15, wherein the processing apparatus is further operable to transmit graphical user interface data to a display apparatus, the graphical user interface data comprising geographical information depicting at least a portion of the wireless network and an estimate of at least one signal characteristic at the measurement location for the wireless network with the proposed base station added, the at least one signal characteristic being estimated using the first and second data.

21. The apparatus according to claim 20, wherein the at least one signal characteristic comprises at least one of:

the estimated power spectrum density at the measurement location for the wireless network with the proposed base station added;

the estimated signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station within the wireless network with the proposed base station added;

the estimated signal-to-noise ratio for a communication channel at the measurement location transmitted by an existing base station within the wireless network with the proposed base station added;

an indication of the number of handoff states available at the measurement location within the wireless network with the proposed base station added, the number of handoff states equalling the number of estimated signal-to-noise ratios equal to or greater than an acceptable signal threshold level at the measurement location; and

an indication of whether a wireless device at the measurement location within the wireless network with the proposed base station added would have an acceptable number of handoff states.

22. An apparatus for analysing a wireless network with a proposed base station added at a proposed location, the apparatus comprising:

an input device operable to receive first and second data, wherein the first data comprises a signal strength for a test signal received at each of a plurality of measurement locations from a test transmitter at the proposed location, wherein the second data comprises a power spectrum density indication at each of the measurement locations for the existing wireless network, and wherein the second data further comprises existing base station data comprising signal strengths for a plurality of communication signals received at each of the measurement locations, each communication signal corresponding to a respective one of a plurality of communication channels transmitted by one or more existing base stations within the wireless network;

a processing apparatus, coupled to the input device, operable to estimate a power spectrum density at each of the measurement locations for the wireless network with the proposed base station added using the respective first and second data;

wherein the processing apparatus is further operable to estimate, for each of the measurement locations, a signal-to-noise ratio for a communication channel transmitted by the proposed base station using the respective first data and the estimate of the power spectrum density at the particular measurement location for the wireless network with the proposed base station added;

and wherein the processing apparatus is further operable to estimate, for each particular one of the measurement locations, a signal-to-noise ratio for each of the plurality of communication channels transmitted by one of the existing base stations using the existing base station data and the estimate of the power spectrum density at the particular measurement location for the wireless network with the proposed base station added;

and wherein the processing apparatus is further operable to estimate for each particular one of the measurement locations, the number of handoff states available to a wireless device at the particular measurement location within the wireless network with the proposed base station added by counting the number of communication channels at the particular measurement location transmitted by the proposed base station or one of the existing base stations that have an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

23. The apparatus according to claim 22, wherein the processing apparatus is further operable to transmit graphical user interface data to a display apparatus, the graphical user interface data comprising geographical information depicting at least a portion of the wireless network and an estimate of at least one signal characteristic at one or more of the measurement locations for the wireless network with the proposed base station added, the at least one signal characteristic being estimated using the first and second data.

24. The apparatus according to claim 23, wherein the at least one signal characteristic at a particular one of the measurement locations comprises at least one of:

the estimated power spectrum density at the particular measurement location for the wireless network with the proposed base station added;

the estimated signal-to-noise ratio for a communication channel at the particular measurement location transmitted by the proposed base station within the wireless network with the proposed base station added;

the estimated signal-to-noise ratio for a communication channel at the particular measurement location transmitted by an existing base station within the wireless network with the proposed base station added;

an indication of the number of handoff states available at the particular measurement location within the wireless network with the proposed base station added, the number of handoff states equalling the number of estimated signal-to-noise ratios equal to or greater than an acceptable signal threshold level at the particular measurement location; and

an indication of whether a wireless device at the particular measurement location within the wireless network with the proposed base station added would have an acceptable number of handoff states.

25. A non-transitory computer readable media tangibly embodying a program of instructions executable by a computing apparatus to perform the steps of:

receiving first data representative of a test signal received at a measurement location from a test transmitter at the proposed location, wherein the first data comprises a signal strength for the test signal received at the measurement location;

receiving second data representative of at least one communication signal received at the measurement location from the existing wireless network, wherein the second data comprises a power spectrum density indication for the existing wireless network at the measurement location and a signal strength for at least one communication signal received at the measurement location from at least one existing base station within the wireless network;

processing the first and second data to estimate at least one signal characteristic at the measurement location for the wireless network with the proposed base station added, wherein the processing the first and second data comprises;

estimating a test signal strength for a signal received at the measurement location from the proposed base station using the signal strength for the test signal,

estimating a power spectrum density at the measurement location for the wireless network with the proposed base station added using the power spectrum density indication for the existing wireless network at the measurement location and an estimate of a total signal strength for a signal received at the measurement location from the proposed base station;

estimating a signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station using the estimate of the test signal strength for a signal received at the measurement location from the proposed base station and the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added;

estimating a signal-to-noise ratio for a communication channel at the measurement location transmitted by the existing base station using the signal strength for the communication signal received at the measurement location from the existing base station and the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added;

estimating the number of handoff states available to a wireless device at the measurement location within the wireless network with the proposed base station added by counting the number of communication channels at the measurement location transmitted by the proposed base station or one of the existing base stations that have an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level.

26. A method for analysing a wireless network with a proposed base station added at a proposed location, the method comprising:

receiving first data comprising a signal strength for a test signal received at a measurement location from a test transmitter at the proposed location;

receiving second data comprising a power spectrum density indication for the existing wireless network at the measurement location and signal strengths for a plurality of communication signals received at the measurement location, each communication signal corresponding to a respective one of a plurality of communication channels transmitted by one or more existing base stations within the wireless network;

estimating a test signal strength for a signal received at the measurement location from the proposed base station using the signal strength for the test signal;

estimating a power spectrum density at the measurement location for the wireless network with the proposed base station added using the power spectrum density indication for the existing wireless network at the measurement location and an estimate of a total signal strength for a signal received at the measurement location from the proposed base station;

estimating a signal-to-noise ratio for a communication channel at the measurement location transmitted by the proposed base station by dividing the estimate of the test signal strength for a signal received at the measurement location from the proposed base station by the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added; and

estimating a signal-to-noise ratio for each of the plurality of communication channels at the measurement location, each signal-to-noise ratio comprising the signal strength for the respective communication signal received at the measurement location from the corresponding existing base station divided by the estimate of the power spectrum density at the measurement location for the wireless network with the proposed base station added;

estimating the number of handoff states available to a wireless device at the measurement location within the wireless network with the proposed base station added by counting the number of communication channels at the measurement location transmitted by the proposed base station or one of the existing base stations that have an estimated signal-to-noise ratio equal to or greater than an acceptable signal threshold level; and

estimating if a wireless device at the measurement location would have an acceptable number of handoff states, wherein an acceptable number of handoff states is between one and an acceptable maximum threshold level of handoff states.