Site survey for wireless base station placement

Patent metadata

Field	Value
Publication number	US-11272377-B1
Application number	US-202016798307-A
Country	US
Kind code	B1
Filing date	Feb 22, 2020
Priority date	Feb 22, 2020
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

Apparatuses, methods, and systems for surveying a site are disclosed. One method includes transmitting, by a ground unit, wireless signals while a directionally adjustable beam-forming antenna of the ground unit changes a beam direction of the transmission of the wireless signals to N beam directions, wherein the directionally adjustable beam-forming antenna includes a known motion, receiving and measuring, by an elevated unit, a magnitude and phase of the wireless signals transmitted by the ground unit through the N beam directions, determining N complex receive power representations wherein each complex receive power representation includes the measured magnitude and phase of the received wireless signals corresponding with each of the N beam directions, and determining a receive power summation comprising performing a complex summation of the N complex receive power representations.

First claim

What is claimed:

1. A method of surveying a site, comprising:
transmitting, by a ground unit, wireless signals while a directionally adjustable beam-forming antenna of the ground unit changes a beam direction of the transmission of the wireless signals to N beam directions, wherein the directionally adjustable beam-forming antenna includes a known motion that includes the directionally adjustable beam-forming antenna changing directions at a predetermined rate and each of N beam directions being uniformly separated from each other;
receiving and measuring, by an elevated unit, a magnitude and phase of the wireless signals transmitted by the ground unit through the N beam directions;
determining N complex receive power representations wherein each complex receive power representation includes the measured magnitude and phase of the received wireless signals corresponding with each of the N beam directions; and
determining a receive power summation comprising performing a complex summation of the N complex receive power representations.

2. The method of claim 1 , further comprising designating a location of the ground unit as in-range of a base station at a location of the elevated unit if the determined receive power summation is greater than a predetermined threshold level.

3. The method of claim 1 , wherein the elevated unit includes an omni-directional antenna.

4. The method of claim 1 , wherein the receive power summation is determined at multiple locations of the ground unit.

5. The method of claim 1 , wherein the receive power summation is determined at multiple elevations of the elevated unit or at multiple locations of the elevation platform.

6. The method of claim 1 , wherein the directionally adjustable beam-forming antenna of the ground unit changes a beam direction of the transmission of the wireless signals over a full azimuth sweep of 360 degrees.

7. The method of claim 1 , wherein the directionally adjustable beam-forming antenna of the ground unit changes a beam direction of the transmission of the wireless signals over an elevation sweep of 180 degrees.

8. The method of claim 1 , wherein the directionally adjustable beam-forming antenna of the ground unit comprises a dish antenna.

9. The method of claim 1 , wherein determining the receive power summation further comprises determining a power azimuth spectrum (PAS) for each of the N beam directions, comprising for each one of the N beam directions:
estimating the PAS based on the known motion of the adjustable beam-forming antenna, a known beam-forming pattern of the adjustable beam-forming antenna, and the measured phase and amplitude of the received wireless signals of the one of the N beam directions comprising:
transforming values of the measured phase and amplitude of the received wireless signals of the one of the N beam directions and the known beam-forming pattern into a frequency domain;
performing a power azimuth angular spectrum estimation in the frequency domain; and
transforming the estimated power azimuth angular spectrum back to a time domain.

10. The method of claim 9 , further comprising performing a complex summation of the PAS of the each of the N beam directions.

11. The method of claim 9 , wherein performing the power azimuth angular spectrum estimation in the frequency domain, comprises:
removing frequency domain samples of the known beam-forming pattern having zero values;
removing frequency domain samples of the measured phase and amplitude of the received wireless signals that correspond with the removed frequency domain samples of the known beam-forming pattern;
dividing the frequency domain samples of the measured phase and amplitude of the received wireless signals with the frequency domain samples of the known beam-forming pattern for a frequency bin of each sample after removing the frequency domain samples.

12. The method of claim 9 , wherein estimating the power azimuth angular spectrum of the surveyed site based on the known motion of the adjustable beam-forming antenna, the known beam-forming pattern of the adjustable beam-forming antenna, and the measured phase and amplitude of the received wireless signals comprises:
estimating the power azimuth angular spectrum, comprising:
determining an FFT (fast Fourier transform) of the measured phase and amplitude of the received wireless signals;
determining an FFT of an antenna radiation pattern of the adjustable beam-forming antenna;
frequency domain windowing the FFT of the measured phase and amplitude of the received wireless signals;
frequency domain windowing the FFT of an antenna radiation pattern of the adjustable beam-forming antenna;
frequency domain estimating the frequency domain windowing the FFT of the measured phase and amplitude and the frequency domain windowing the FFT of an antenna radiation pattern; and
determining and IFFT (inverse fast Fourier transform) of the frequency domain estimate.

13. A site survey tool, comprising:
a ground unit operating to transmit wireless signals while a directionally adjustable beam-forming antenna of the ground unit changes a beam direction of the transmission of the wireless signals to N beam directions, wherein the directionally adjustable beam-forming antenna includes a known motion that includes the directionally adjustable beam-forming antenna changing directions at a predetermined rate and each of N beam directions being uniformly separated from each other;
an elevated unit operating to receive and measure a magnitude and phase of the wireless signals transmitted by the ground unit through the N beam directions;
a controller operating to:
determine N complex receive power representations wherein each complex receive power representation includes the measured magnitude and phase of the received wireless signals corresponding with each of the N beam directions;
determine a receive power summation comprising performing a complex summation of the N complex receive power representations.

14. The site survey tool of claim 13 , wherein the controller is further operative to designate a location of the ground unit as in-range of a base station at a location of the elevated unit if the determined receive power summation is greater than a predetermined threshold level.

15. The site survey tool of claim 13 , wherein the receive power summation is determined at multiple locations of the ground unit.

16. The site survey tool of claim 13 , wherein the receive power summation is determined at multiple elevations of the elevated unit or at multiple locations of the elevation platform.

17. The site survey tool of claim 13 , wherein determining the receive power summation further comprises determining a power azimuth spectrum (PAS) for each of the N beam directions, comprising for each one of the N beam directions, the controller operating to:
estimate the PAS based on the known motion of the adjustable beam-forming antenna, a known beam-forming pattern of the adjustable beam-forming antenna, and the measured phase and amplitude of the received wireless signals of the one of the N beam directions comprising:
transform values of the measured phase and amplitude of the received wireless signals of the one of the N beam directions and the known beam-forming pattern into a frequency domain;
perform a power azimuth angular spectrum estimation in the frequency domain; and
transform the estimated power azimuth angular spectrum back to a time domain.

18. The site survey tool of claim 17 , wherein the controller further operates to perform a complex sum

Assignees

• Meta Platforms Inc

Inventors

• Bondalapati Pratheep
• Tiwari Abhishek
• Ramakrishnan Rohan
• Pham Duong
• Kusuma Julius
• Tabatabai Farbod
• Yazdan Ali

Classifications

• H04W16/18 Primary

  Network planning tools · CPC title

• H04B17/318 Primary

  Received signal strength · CPC title

• H04B7/0617

  for beam forming · CPC title

• H04W16/28

  using beam steering · CPC title

• H04B7/086

  using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming · CPC title