Browse Prior Art Database

An efficient method of distributing large size data

IP.com Disclosure Number: IPCOM000242415D
Original Publication Date: 2015-Jul-13
Included in the Prior Art Database: 2015-Jul-13
Document File: 5 page(s) / 317K

Publishing Venue

Motorola

Related People

Feng, Kevin: INVENTOR [+5]

Abstract

An efficient method for distributing large size data to a plurality of destination devices in a two way radio communication system is provided. By this method, the source device repeatedly transmits the large size data in a sequence of data packets; the plurality of destination devices detect its individual missing status of data packet transmission, and feedback the status to the source when a certain conditions matched; based on all the received status from receivers, the source device then prioritizes certain fragments of the large message during the retransmission cycles.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 36% of the total text.

An efficient method of distributing large size data by dynamically adjusting sequence based on real-time missing status of receivers

By Kevin Feng, Fisher Fei, Yahui Gong, Dixen Chen, Matthew Tian

Motorola Solutions

 

ABSTRACT

An efficient method for distributing large size data to a plurality of destination devices in a two way radio communication system is provided. By this method, the source device repeatedly transmits the large size data in a sequence of data packets; the plurality of destination devices detect its individual missing status of data packet transmission, and feedback the status to the source when a certain conditions matched; based on all the received status from receivers, the source device then prioritizes certain fragments of the large message during the retransmission cycles.

PROBLEM

Today in the two way radio communication system, data application is becoming more and more popular, transmission of large-size data is more and more needed for e.g. remote upgrading firmware or codeplug for a plurality of radio subscribers, distributing high-definition images or other types of large files to a group of subscribers and etc.

Such data application brings a problem for narrow band system due to low capacity in such system. Taking ASTRO P25 system as example, the subscriber firmware is about 35 megabytes; while data channel transmitting speed is about 96 kilobits per second. The complete firmware is split to a number of single data packets for sequentially transmission. It may take several hours to receive all the data fractions from source without any interruption to the transmission. If the transmission is interrupted, for e.g. the signal fades out on the RF link, subscriber engaged into voice transmission, or the change of the network condition, it has to wait for another couple of hours or even more to try to recover the missing part.

An extreme example is that when only one of a bunch of destination devices missed one single packet, can be the last one, the source device has to send another round of all packets even most of transmission are wastes as already being received. This will become worse and annoy the user a lot when the RF is not quite stable, or voice call occasionally occurs, as the subscriber is keeping receiving data for long time.

SOLUTION

The idea is when distributing a plurality of data packets to a plurality of devices,  all the data packets are put in order and transmitted by the central(source) device, each individual device(destination) tracks and reports its receiving status(when necessary ) in real time; based on the real-time status the source device then dynamically adjusts the sending order of subsequent packets, this way those destination devices that only miss a fraction of packets can get the missed part earlier and finish the receiving earlier, hence improves the efficiency of the whole distributing:

1.    Source device transmits all sequential data packets to a group of destination devices repeat...