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The patents were discovered by Apple Insider's Mikey Campbell.
The two patents are for "automatic identification of vehicle location" and "vehicle location in weak location signal scenarios." They could allow iPhone users to establish connections with compatible vehicles - likely through the company's fledgling CarPlay program (formerly iOS in the Car) - so the owner's device can learn where the car is.
Once that initial "pairing" is complete, which can simply be triggered by first entering the car or turning on the vehicle's ignition, the car can then transmit important information to the iPhone via Bluetooth.
When the iPhone knows the car is parked, this connection will continually plot the movement of the iPhone as they walk away from the vehicle. Thanks to a combination of sensors and signals, including the iPhone's accelerometer, Bluetooth, and/or GPS, the system can determine your direction, motion, and speed relative to the car.
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As for getting back to the car, Apple describes how users can simply command Siri to "Find my car," which will pull up a quick navigation route to your car using a map and audio directions.
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It's unclear if Apple plans to release this feature as part of iOS 8 later this fall. In June, 9to5Mac discovered that Apple was testing a new iOS 8 feature that would help iPhone 5S users navigate back to their parked vehicles. With the help of the Maps application, users could simply drop a parking pin on the location where they parked their car, and use the same app to find a turn-by-turn route back to their car.
Using the iPhone 5S' M7 coprocessor - which pulls data from the iPhone's various sensors such as the accelerometer, gyroscope, and compass - the phone could even tell the difference between a parked and stopped car by noting when a car door is slammed shut.
Here's more of what you can expect in Apple's upcoming iOS 8.