The concept of signal interference is well known in the field of communications, and, more specifically, wireless communications. Many situations exist where signal interference between multiple wireless devices degrades the performance of one or more of the devices, based on signal strengths and/or the physical proximity of the devices.
For example, in the home, signals from a microwave oven, cordless phone, and wireless access point often interfere with each other. Depending on the relative strengths of the signals (i.e., weaker signals introduce less interference) and/or physical separation between the devices (i.e., signals weaken as the distance between the devices increases), the interference results in a slow download, the inability to communicate with a Web server, or a “bad” phone connection (i.e., unable to clearly hear the other party).
In some situations, the interference may be of little consequence, though annoying to most users. However, there are situations, such as those dealing with the wireless communication devices used by public safety personnel, where the interference has potentially problematic consequences, particularly when working in a hazardous environment.
For example, a police officer typically uses a two-way radio for communicating with a dispatcher or other officers on the same digital radio frequency. These digital radio communications are subject to interference by other wireless devices (e.g., cell phones, vehicular subscriber modems, etc.) that operate on nearby spectrum blocks, when the officer is near to these wireless devices. In such a situation, the officer's time-sensitive communications may become unclear, completely garbled, or delayed.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.