Short range devices in the 433 MHz band

433 MHz short range devices will be considered at the next SE24 meeting in Mainz on September 1-2.

The CEPT's Spectrum Engineering Working Group SE24 deals with Short Range Devices. The input documents for the meeting have now been made available on the European Radiocommunications Office (ERO) website.

One of the documents is 'Short Range Devices in the 433 MHz band'. It deals with licence exempt voice operating that is currently permitted in this band.

Document Summary
The frequency band 433.05 - 434.79 MHz has been opened for voice applications provided that a spectrum access technique such as LBT [Listen Before Transmit] or equivalent is used (see note 4bis of Annex 1 to ERC REC 70-03).

In contributions to the SE24 consideration of Maximising spectrum use efficiency it has been concluded that LBT mitigation technique does not provide acceptable functionality for short burst transmissions. Furthermore applications with short burst transmissions can not coexist with LBT applications on the same channel because of timing and LBT receivers are not sensitive enough to detect the automotive signals..

As mentioned in document M44_22RO_SE24 the new regulation allowing voice applications in the 433 MHz band has led to development of equipment combining PMR 446 (8 channels) with additional 69 channels for 433 MHz operation.

The 433 MHz band is currently used for a wide range of SRD applications including automotive applications, alarms and home automation The increasing use of voice applications in this band is creating interference and blocking in contradiction to the intention of the regulation allowing voice applications which was based on the principle of allowing equal access and sharing of all SRDs in this band.

As justified in contributions to the SE24 studies regarding Maximising spectrum use efficiency it is suggested that the SE24 propose changes to the regulation in Annex 1 to ERC REC 70-03 allowing voice applications in the 433 MHz band.

Document Proposal
It is suggested that the SE24 in its report to SRD/MG make proposals for reconsideration of the mitigation techniques within the frequency band 433.05-434.79 MHz in order to limit the current and future interference to existing short burst SRD applications within this band.

This change should be implemented as soon as possible.

The Input documents to SE24 Meeting 42 in Mainz can be found by following these steps:

1. Go to the ERO home page http://www.ero.dk/

2. Under 'ECC Activities' select 'Meeting Documents'

3. In 'Select Group: ' select 'SE24'

4. In 'Select Year: ' select '2008'

5. Expand SE24_M45_September 2008 Mainz

6. Expand 'Input'

7. Tick all the documents you wish to download

8. Click on the 'download Selected' button (top right)

New Citizens Band allocated within the Amateur Radio 70cm band ?
http://www.southgatearc.org/news/july2008/
cb_on_70cms.htm