Browse Prior Art Database

SIMPLEX MOBILE TRANSMITTER ROAMING INDICATION

IP.com Disclosure Number: IPCOM000008874D
Original Publication Date: 1998-Sep-01
Included in the Prior Art Database: 2002-Jul-19
Document File: 2 page(s) / 93K

Publishing Venue

Motorola

Related People

Milena Sukovic: AUTHOR [+3]

Abstract

In multiple site frequency digital radio systems, the selection of the best site can be of utmost impor- tance. Many designs exist for full duplex subscribers and more limited designs exist for half-duplex radios. Typically these half-duplex devices have designs that allow site selection while receiving but not while transmitting. This means that if a transmit- ting device moves out of the coverage area, then the user who is transmitting does not know if his/her audio is intelligible at the receiving base site. On the next page is a method that can be used to overcome this site selection limitation in half-duplex sub- scriber devices. 2. Upon this voice gap detection, the subscriber will insert a Signal Check Request pattern instead of the silent voice information, 3. If the user unexpectedly generates voice (starts talking) during this roam check signalling sequence, then that voice is buffered and sent out following the roam check signalling sequence.

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MOlOROLA Technical Developments

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SIMPLEX MOBILE TRANSMITTER ROAMING INDICATION

by Milena Sukovic, Robb Biggs, George Liburd

PROBLEM

  In multiple site frequency digital radio systems, the selection of the best site can be of utmost impor- tance. Many designs exist for full duplex subscribers and more limited designs exist for half-duplex radios. Typically these half-duplex devices have designs that allow site selection while receiving but not while transmitting. This means that if a transmit- ting device moves out of the coverage area, then the user who is transmitting does not know if his/her audio is intelligible at the receiving base site. On the next page is a method that can be used to overcome this site selection limitation in half-duplex sub- scriber devices.

2. Upon this voice gap detection, the subscriber will insert a Signal Check Request pattern instead of the silent voice information,

3. If the user unexpectedly generates voice (starts talking) during this roam check signalling sequence, then that voice is buffered and sent out following the roam check signalling sequence.

4. After the subscriber has transmitted the Signal Check Request, it will move to its receive frequen- cy. During this time the base site will have received the subscriber's Signal Check Request, processed it, and sent back a response.

5. The subscriber will wait to receive signal infor- mation for some time interval.

6. Depending upon the received indication or lack thereof, the SU will either do nothing or will alert th user that his/her audio is not being heard at the receiving end.

Note: More sophisticated responses which may include further roaming instructions to the SU may be sent at this time.

Note: Usually the inbound (subscriber to base) sig- nal coverage is less than the o...