Calculating transmission anticipation time using dwell and blank time in spread spectrum communications for security systems

• US 7,835,343 B1
• Filed: 03/24/2006
• Issued: 11/16/2010
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: RSI Video Technologies Incorporated (Resideo Technologies, Inc.)
• Original Assignee: RSI Video Technologies Incorporated (Resideo Technologies, Inc.)
• Inventors: Reibel, Jean-Michel
• Primary Examiner(s): Phan; Huy
• Assistant Examiner(s): Magloire; Vladimir
• Application Number:
  US11/389,673
• Time in Patent Office: 1,698 Days
• Field of Search: 455/410, 455/445, 370/347, 370/350, 370/310, 370/324, 370/311, 370/318
• US Class Current: 370/350
• CPC Class Codes: G08B 13/1966 Wireless systems, other than telephone systems, used to communicate with a camera
• CPC Class Codes: G08B 13/19697 Arrangements wherein non-video detectors generate an alarm themselves
• CPC Class Codes: G08B 25/007 Details of data content structure of message packets; data protocols
• CPC Class Codes: G08B 25/10 using wireless transmission systems G08B25/009 takes precedence
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A building-security method is implemented in a variety of embodiments. In one such embodiment, the building-security method is implemented for bidirectional, wireless communication between a control panel device and peripheral devices. Each of the devices includes a wireless communication circuit to effect wireless communications. The control panel wirelessly sends synchronization information to at least one of the peripheral devices. Power consumption is reduced for at least one of the wireless communication circuits by coordinating a communications time interval and a selected channel for communication between the control panel device and the peripheral device to effect wireless communications between the control panel and the peripheral device. The selected channel is one channel from a sequence of channels used for wireless communications between the control panel device and the peripheral devices.

Claims

1. For use in a building-security system, a method for wireless communication between a control panel device and peripheral devices, each of the devices including a wireless communication circuit to effect wireless communications between the control panel device and the peripheral devices, the method comprising:

to effect wireless communications between the control panel device and at least one of the peripheral devices, providing communication intervals to define communication therebetween, the communications intervals defined as a function of a selected one of multiple frequencies for communicating between the control panel device and said at least one peripheral device;

communicating between the control panel device and said at least one peripheral device based on the communication intervals of at least said selected one of the multiple frequencies;

reducing power consumption in at least one of the control panel device and said at least one peripheral device as a function of the communication intervals and said selected one of the multiple frequencies;

synchronizing the control panel device and peripheral devices using periodic wireless communications and a local clock circuit for each of the control panel device and peripheral devices;

calculating a transmission anticipation time from,

a sequence of the multiple frequencies used for communications between the control panel device and peripheral devices,

the number of frequencies in the sequence between said selected one of the multiple frequencies and a current transmission frequency of the multiple frequencies,

a dwell time of the control panel device and peripheral devices, and

a blank time of the control panel device and peripheral devices; and

transmitting in response to the transmission anticipation time and an expected activation time of the control panel device,

wherein said at least one of the devices relies on a limited power source and the control panel device collects building-security data from the peripheral devices while mitigating power consumption from the limited power source.

2. The method of claim 1, wherein the reducing power consumption is also a function of a sequence of the multiple frequencies and a second selected one of the multiple frequencies.

3. The method of claim 1, further including the step of communicating, between the control panel device and the peripheral devices, data representing a current time index that is used as a reference for establishing communication timings between the devices.

4. The method of claim 3 further including the steps of:

detecting a loss of synchronization between the control panel device and said at least one of the peripheral devices; and

increasing a receive activation time of one of the devices in response to the detection.

5. The method of claim 1, wherein said selected one of the multiple frequencies corresponds to an initial frequency for receiving wireless communications from said at least one peripheral device.

6. The method of claim 1, wherein the effecting wireless communications between the control panel device and the peripheral devices is implemented using frequency-hopping spread spectrum.

7. The method of claim 1, further including the step of transmitting messages between the devices wherein the messages use a short frame and a long frame.

8. The method of claim 7, further including the step of transmitting the long frames in packets that contain a number of frames that is an integer multiple of the number of different frequencies of said multiple frequencies.