Patent Application
20120223810
The subject invention relates to vehicles and, more particularly, to controlling aspects of a vehicle from a remote location.
Remote keyless systems (RKS) are designed to control the operation of aspects of a vehicle or other machine based on a signal received from a remote control device. Some remote keyless entry systems include both a remote keyless entry system (RKE) and a remote keyless ignition system (RKI).
An RKE allows access to a vehicle based on one or more signals received from a remote control device. In some cases, the remote control device is integrated in to a unit that also includes the key to the vehicle. Regardless of how implemented, the remote control device can be utilized to lock or unlock power door locks without physical contact and from a distance away from the vehicle. Similarly, an RKI allows the vehicle to be started without physical contact with the vehicle.
RKE's and RKI's are becoming more common in automobiles as either an initial feature or as an after market add-on. Historically, RKS's employed a stand alone or dedicated antenna structure in either the front windshield or in the back glass to receive signals from the remote control device. The standalone antenna is typically mounted on or near the front windshield and can cause interference with other systems located near it. In some cases, the antenna can be located on the back glass but this increases cost and also can degrade the FM antenna performance due to capacitive coupling between the FM antenna and the RKS antenna as well as detuning the FM antenna.
Accordingly, it is desirable to provide a way to provide an RKS that avoids or reduces one or more of the drawbacks described above.
In one exemplary embodiment of the present invention, a remote keyless system is disclosed. The remote keyless system of this embodiment includes a remote control device configured to create a signal having at least a component at a first frequency and an antenna assembly coupled to a vehicle, the antenna assembly including a first antenna tuned to receive a signal in a frequency band. The remote keyless system of this embodiment also includes a first filter coupled to the first antenna and configured to pass the first frequency, a second filter coupled to the first antenna and configured to pass the frequency band and a remote keyless system controller coupled to the first filter that, upon receipt of a predetermined signal, causes the vehicle to perform an action. In this embodiment, the first frequency is an integer multiple of a frequency in the frequency band.
In another exemplary embodiment of the present invention, a vehicle that includes remote keyless system controller configured to receive a signal having a first frequency and to cause the vehicle to perform an action is disclosed. The vehicle of this embodiment also includes an antenna assembly coupled to the vehicle tuned to receive a signal in a frequency band and a first filter coupled to the first antenna and configured to pass the first frequency. The vehicle also includes a second filter coupled to the first antenna and configured to pass the frequency band. The first frequency is an integer multiple of a frequency in the frequency band.
The above features and advantages and other features and advantages of the invention are readily apparent from the following detailed description of the invention when taken in connection with the accompanying drawings.
Other features, advantages and details appear, by way of example only, in the following detailed description of embodiments, the detailed description referring to the drawings in which:
The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
In accordance with an exemplary embodiment of the invention a system for remote control of either or both an RKE or an RKI (collectively or individually referred to herein as an RKS) for a vehicle is disclosed. The system does not require an additional antenna structure beyond the FM antenna structure utilized by the vehicle to receive FM radio. In one embodiment, the RKS transmits information from a remote control device to the vehicle on a carrier signal having a frequency of or about 315 MHz. In a particular embodiment, the remote control transmits data on a carrier signal having a frequency of 314.9 MHz The carrier frequency is detectable by the FM antenna of the typical vehicle as it represents the third harmonic of a 105 MHz signal. A 105 MHz signal falls within the FM radio frequency band of 87.5 to 108.0 MHz. Of course, remote control devices that operate at other than about 315 MHz are within the scope of the invention as long as the signal is a harmonic of a signal in the FM band.
Turning now to
The remote control device 102 can take many forms and needs only to broadcast a signal that may ultimately be received by the vehicle 104. In one embodiment, the remote control device 102 can be a transmitter that includes one or more buttons 110 that, when activated, cause it to transmit a signal over the wireless connection 106 (e.g., air). The signals are received by the vehicle 104 and cause it perform certain actions. For example, the signals can cause the engine of the vehicle 104 to start, the doors to lock or unlock, the trunk to open, an alarm to be activated or deactivated, windows of the vehicle to open or close, the horn to sound, or any other function. According to one embodiment, the signals are transmitted as radio waves at or about 315 MHz. In another embodiment, the signals are transmitted at any frequency that is an integer multiple of any frequency in the range between 87.5 and 108.0 MHz. For example, the signals transmitted by the remote control device 102 could be the second, third, fourth, etc, harmonic of any signal in the range between 87.5 and 108.0 MHz.
In one embodiment, the antenna assembly 204 can receive either or both AM and FM radio waves. In one embodiment, the antenna assembly 204 is tuned to receive FM radio waves in the FM radio band of about 87.5 to 108.0 MHz. In one embodiment, the antenna assembly can provide heat to the back glass 202 to defrost it. As illustrated, the antenna assembly 204 includes a plurality of traces 206 that collectively, form the assembly. The traces 206 are formed of metal or another suitable material for receiving radio waves.
The antenna assembly 204 is coupled via connection 208 to an amplifier 210. The connection 208 is a pig tail connection in one embodiment. One output of the amplifier 210 is coupled to an RKS receiver module 212 that decodes the signal received by the antenna assembly 204 (and possibly amplified or otherwise adjusted by the amplifier 210) from the remote control device 102 (
The antenna assembly 204 may include both an FM antenna 301 and an AM antenna 302. The antenna assembly 204 can be formed in many different manners as is known in the art. The FM antenna 301 is coupled to two filters 303, 304. The first filter 303 is tuned to pass frequencies surrounding the frequency at which the remote control device 102 (
The second filter 304 is coupled to an FM amplifier 310 and the third filter is coupled to an AM amplifier 312. The outputs of these two amplifiers 310, 312 are provided to the radio receiver 330. Of course, other elements could be provided between the amplifiers 310, 312 to isolate the signals from one another or they could be separately coupled to the radio receiver 330.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed for carrying out this invention, but that the invention will include all embodiments falling within the scope of the present application.
