US-12627364-B2 - Security communicator dual antenna system

Abstract

A fire, burglary or access control security communicator having an antenna switching system and method that is external to the cell module to allow complete switching from a primary to a secondary antenna based on signal strength, error rate or other performance parameters.

Inventors

• Richard L. Soloway
• Michael A. Carrieri
• Christopher Summit

Assignees

• NAPCO SECURITY TECHNOLOGIES, INC.

Dates

Publication Date

20260512

Application Date

20220823

Claims (18)

1. 1 . A communication system comprising: a single RF feed input, a sole cellular modem having a simple RF feed Input and a single RF feed output, and switch having a single RF feed input and a plurality of RF feed outputs, each of said plurality of RE feed outputs of said switch connected to a single antenna; said sole cellular modem receives said single RF feed input prior to said switch receiving said RF feed input at said single RF feed input of said sole cellular modem; said switch located between said sole cellular modem and said plurality of said antennas, said switch directly connected to said plurality of antennas; said cellular modem does not directly send said RE feed to any of said plurality of antennas and is not directly connected to said antennas; and after said switch receives said single RF feed input at said single fed RE input of said switch, said switch adapted to use said single RE feed output of said switch to connect said single RF feed input to one of said plurality of antennas.
2. 2 . The system of claim 1 further including a processor, said processor adapted to connect one of said plurality of antennas to said input of said cellular modem based upon said connected antenna having an optimal performance parameter compared to other of said plurality of antennas.
3. 3 . The system of claim 2 wherein said performance parameter is signal strength.
4. 4 . The system of claim 2 wherein said performance parameter is error rate.
5. 5 . The system of claim 2 wherein said processor uses logic control to select one of said plurality of antennas to said input of said cellular modem.
6. 6 . The system of claim 2 wherein said processor uses antenna switching logic to select one of said plurality of antennas to said input of said cellular modem.
7. 7 . The system of claim 2 wherein said processor uses logic control and antenna switching logic to select one of said plurality of antennas to said input of said cellular modem.
8. 8 . The system of claim 2 wherein said processor receiver antenna performance data from a cellular modem.
9. 9 . The system of claim 2 wherein said processor receiver antenna signal strength data from a cellular modem.
10. 10 . The system of claim 2 wherein said processor receiver antenna error rate data from a cellular modem.
11. 11 . The system of claim 1 further adapted to receive antenna performance data from said cellular modem.
12. 12 . The system of claim 1 further adapted to receive antenna signal strength data from said cellular modem.
13. 13 . The system of claim 1 further adapted to receive antenna error rate data from a cellular modem.
14. 14 . The system of claim 1 further adapted to isolate an inoperable antenna in the system.
15. 15 . The system of claim 1 wherein said antennas have differing polarizations.
16. 16 . The system of claim 1 wherein said antennas one of said antennas has a vertical polarization and another of said antennas has a horizontal polarization.
17. 17 . The system of claim 1 having different directional antennas.
18. 18 . The system of claim 1 wherein said modem cannot select a specific antenna or combine signals from two or more antennas.

Description

RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63/236,212, filed on Aug. 23, 2021, which is incorporated herein in its entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT Not applicable. INCORPORATION BY REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC Not applicable. BACKGROUND OF THE INVENTION RF radio transmissions often create nulls or other signal suppressing reflections which affect the ability to properly transmit or receive signals targeted to a single antenna. Antenna diversity is often used whereby there are multiple receive/transmit antennas spaced a distance apart so that a null on one antenna can be avoided by using another antenna. Cell tower communications standards, such as the 3GPP specification, have defined antenna configurations such as MIMO (multiple in and multiple out) and MISO (multiple in single out) where multiple antennas can be used to improve throughput by doing simultaneous reception (multiple in) but also provide avoidance of or minimization of nulls. Typically, the signals from two antennas are blended together. Cell phones typically have multiple antennas but have trouble obtaining true diversity because they cannot space the antennas far enough apart, according to scientific wavelength calculations, in their small housing size. However, a cell phone user can easily turn or move to improve reception, which is like having a wider spacing between antennas. Technologies such as 2G and 3G all utilized single antennas as defined by the 3GPP standards and implemented by the manufacturers of cell modems. The 4G LTE (long term evolution) network was developed to support multiple antennas in MIMO and MISO configurations. These configurations have active circuitry in the cell modules that either combines two weak signals together or provides two totally independent inbound streams for speed and reception enhancement. However, LTE Category M (CAT-M) and NBIoT standards required increased receiver sensitivity in place of multiple antenna technology as a means to reduce cost. As a result, CAT-M or NBIoT cell modules have only a single antenna port for cell based communication. Cellular radio communication devices installed in, in use of, or connected to fire, burglary and access control systems, which are fixed to a specific location, such as being mounted on a wall, are not movable. Thus, if a low signal condition occurs, there is no automatic method to resolve the problem. This low signal condition could occur because of environmental changes, such as the equipment being moved near the radio or an obstruction blocking the signal, such as a large truck, which could introduce new null patterns which were not present at the time the radio was installed. Even leaves on trees that were not there in the winter, but grew in the summer, could create a low signal condition. Also, fire alarms with their cell radios are typically mounted on ground floors in buildings and remain fixed in-place. This makes the system susceptible to a degradation of reception and propagation signals as a result of unforeseen changes. For example, other building may be constructed that disrupt or degrade cellular communications. Even the growth of trees of long periods of time may degrade cellular communication Thus, as will be discussed in further detail below, the dual diversity radio antennas of the present invention improve communications of critical systems such as fire, intrusion, security and medical alarm systems. BRIEF SUMMARY OF THE INVENTION In one embodiment, the present invention provides a fire, burglary or access control security communicator having an antenna switching system and method that is external to the cell module to allow complete switching from a primary to a secondary antenna based on signal strength, error rate or other performance parameters. In another embodiment, the present invention provides a communicator having an antenna switching system that does not require direct support from the cell module manufacturer and can be applied to any cell module. In another embodiment, the present invention provides a communicator having an antenna switching system capable of isolating an inoperable antenna in the system. In another embodiment, the present invention provides a communicator having an antenna switching system deploying antennas with differing polarizations. In another embodiment, the present invention provides a communicator having an antenna switching system deploying antennas with vertical and horizontal polarizations. In another embodiment, the present invention provides a communicator having an antenna switching system that adaptively selects for use an antenna having the best polarization at the time. In another embodiment, the present invention provides a communicator having an antenna switching system deploying antennas pointed in different directions. In another embodiment, the present invention provides a commun