Bi-directional communication system for logistic tracking

Abstract

The present invention provides a method of operating a bi-directional communication system between a plurality of communication devices, which comprises at least one communication controller and a plurality of nodes including a first node. The method includes periodically broadcasting a beacon signal from said communication controller at a broadcast interval via a channel of a first host. The beacon signal contains a first address of the communication controller. The method further includes periodically scanning the beacon signal on the first host by the first node. Upon detecting of the beacon signal by the first node, the first node transmits an identification payload to the communication controller. Upon receipt of the identification payload by the communication controller, an acknowledgement signal is transmitted to the first node.

Description

FIELD OF THE INVENTION[0001]The present invention relates generally to methods of logistic management using bi-directional wireless communication system, and more particularly, to methods of monitoring the location of inventories based on active RFID technology with reduced power consumption in RFID tags and handshaking communication protocol.BACKGROUND TO THE INVENTION[0002]Traditional logistics tracking systems based on RFID technology may be implemented by either active RFID tags or passive RFID tags. Known active RFID tags possess their own power source and transmitter enabling the tag to broadcast its signal. Performance capabilities include longer read ranges and greater memory capacities when compared to passive RFID tags. However, in order to achieve a significant read range and larger memory, these performance capabilities generate a greater demand for power. Typically, active RFID tags are powered by a long life battery that will last for a few years, but will eventually r...

AI Technical Summary

Benefits of technology

The present invention provides a method for operating a bi-directional communication system between a plurality of communication devices using a communication controller and nodes. The communication controller broadcasts a beacon signal at a broadcast interval via a channel of a first host. The beacon signal contains a first address of the communication controller. The nodes scan the beacon signal on the first host and transmit an identification payload to the communication controller upon detection of the beacon signal. The communication controller acknowledges the identification payload with an acknowledgement signal. The method includes periodically broadcasting the beacon signal at multiple timeslots via alternative channels at the same broadcast interval. The system can be used for logistic tracking and includes a communication controller and nodes associated with inventories. The system can also include a local or remote server for collecting and recording the presence information of the nodes.

Problems solved by technology

All these additional features translate to increased costs for the customer.

However, iBeacon utilizing BLE does have its obstacles to overcome if it is to be used for active RFID application.

1. The BLE standard offers 40 frequency channels. Among which only three broadcast channels (37, 38, and 39) can be used for iBeacon applications. This works out to a maximum possible timeslot availability of 400 (based on iBeacon broadcast interval of 100 ms and advertising packet duration of approximately 0.75 msec, i.e. (100 / 0.75)×3 broadcast channels) assuming no collision. For active RFID application with potentially a few thousands active RFID tags to be read by the tag reader, the iBeacon approach for BLE is not workable as the probability of collision increases with increased number of iBeacon tags.

2. The iBeacon approach broadcasts continuously whether the tag reader is present or not. This is a waste of battery life and will increase the rate of active RFID tag replacement cycle which will in turn increase the cost of use. Moreover, the broadcast approach prevents application of RFID on board aeroplanes under FAA rules which restricts equipment RF transmission on aeroplanes in flight.

3. iBeacon approach does not have reliable data handshake between tag and reader. The tag using iBeacon approach does not know whether the tag reader has successfully acquired its data as there is no acknowledgment sent by the reader to the tag. Hence, the tag has to periodically broadcast its data continuously.

4. iBeacon approach is not data secure as any BLE device can sniff and listen to the data broadcast by the tag.

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