Logical link control method based on LLC sub layer of on board unit of Chinese standard ETC system

Abstract

The invention relates to a logical link control method based on an LLC sub layer of an on board unit of a Chinese standard ETC system. In an uplink, a logic link control state machine of the on board unit comprises two types: LLC1 and LLC3, wherein for the LLC1 type, the LLC sub layer receives an interface primitives from the MAC sub layer and gives the notification to the LLC sub layer for requesting the LLC sub layer to transfer data to an application layer, the LLC sub layer receives the interface primitives from the application layer, gives the notification to the LLC sub layer to transfer command sending requests from the application layer, and requests the LLC to transfer data to the MAC sub layer; and for the LLC3 type, the LLC sub layer receives the interface primitives from the MAC sub layer, gives the notification to the LLC sub layer and sends corresponding ACn response to indicate the LLC sub layer to transfer the interface primitives to the application layer, the application layer receives one interface primitive, and the LLC sub layer receives one interface primitive from the application layer, gives the notification to the LLC sub layer to update the internal response data, and indicates the LLC sub layer to transfer the information that whether the updating is succeed or failed to the application layer. The method of the invention has the advantages that the integration degree of circuits is high, the power consumption of the circuits is low, and the information is safer.

Description

technical field [0001] The invention relates to an integrated circuit chip, in particular to a link control method based on the LLC sublayer of the national standard ETC system vehicle unit. Background technique [0002] ETC (Electronic Toll Collection), an electronic toll collection system for short, is an electronic automatic toll collection system for roads, bridges and tunnels that is being developed and promoted internationally. ETC uses dedicated short-range microwave communication technology to exchange information with the on-board unit OBU (On Board Unit) through the toll lane or roadside unit RSU (Road Side Unit) to automatically identify vehicles. A fully automatic charging method that automatically completes the deduction of vehicle tolls by electronic payment. With this system, passing vehicles can pass without stopping at the toll booth to pay the toll, thereby increasing the processing capacity of the toll booth. Because it involves the recovery of investmen...

AI Technical Summary

Problems solved by technology

This vehicle-mounted unit has the following disadvantages: First, there are a large number of unit function modules inside the general integrated circuit, most of which are redundant circuits that are not needed in the vehicle-mounted unit; secondly, each integrated circuit needs to be individually packaged and tested, which increases the number of chips. Cost, the price of imported chips is more expensive, which makes the cost of the vehicle unit higher; in addition, due to the use of general-purpose microprocessors, the working current is relatively large, so that the battery life of the vehicle unit is relatively short

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