A jammer is a device that is used to block signals by jamming Bluetooth or wireless signals for cell phones, GPS signals, and Wi-Fi systems. Jammers flood a specific area with noise that covers the radio bands to be jammed. Jammers can be used for many reasons, such as preventing unwanted calls from telemarketers; as well as keeping people in certain venues, such as restaurants, from using their cell phones in that specific vicinity. Law enforcement and intelligence professionals also have been known to use this technology when dealing with crises such as hostage situations and bomb threats. Despite it's many uses, there are some states that prevent the use of jammers, and this should be checked prior to purchasing one.
Stop using your cell phone carrier if your phone is being jammed. If you have a Voice Over Internet Protocol (VOIP) system installed on your cell phone as an application, then use it in order to get around the jamming radio frequencies. You can use VOIP services on your cell phone that have applications you can download. A couple that come to mind are Vonage and Skype, which can be used to call people independently from your cell phone plan.
Leave the vicinity in which the jammer is being used to prevent radio frequencies in that area. Jammers normally cover up to 30-80 feet of space used to jam radio frequencies in that area. Simply drive or walk away as far as possible from the jamming vicinity in order to regain the use of your electrical device.
Buy a quad band cell phone, which uses four frequencies. Only two frequencies in the United States are used, and the other two are used in the rest of the world. Although it's ideal to use a quad band cell phone, they are still very expensive to get the best reception. The quad band cell phone enables you to switch frequencies on your cell phone, and jammers can only block one frequency at a time.
Change your data plan on your cell phone, GPS and wireless service, as they have different frequencies that can be used as well. 3G, 3Gs and 4G are higher band frequencies than the more widely used ones.
Find out who is jamming the frequencies, and locate where the jammer might be. Either turn the jammer off yourself, or alert the authorities to disable it.