Telecommunications – Radiotelephone system – Including private cordless extension system
Patent
1996-12-16
1999-10-19
Bost, Dwayne D.
Telecommunications
Radiotelephone system
Including private cordless extension system
455423, 379350, H04Q 724
Patent
active
059704152
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a method for handling a collision of an outgoing call from a subscriber unit and a call terminating at a subscriber unit in a radio system providing a wireless local loop. The invention also relates to a subscriber unit of a radio system providing a wireless local loop, the subscriber unit including a terminal equipment and a user interface, the terminal equipment comprising receiver means for receiving radio-frequency signals. The invention further relates to a subscriber network element of a radio system providing a wireless local loop, the subscriber network element having a data transfer connection with a local exchange of a public switched telephone network and comprising means for establishing, via base stations, a radio connection to subscriber units located in the coverage area of the radio system, and for transmitting telecommunication signals between the subscriber units and the local exchange.
The invention relates to a WLL system (Wireless Local Loop), that is, a radio system providing a wireless local loop, in which system subscriber units are connected by a radio connection via base stations and a WLL subscriber network element to a PSTN exchange (Public Switched Telephone Network). Any conventional type of user interface or telephone set can be connected to the WLL system by means of a special terminal equipment, the radio path being thus invisible to the user.
In this connection, a subscriber unit refers to the equipment the subscriber has for transmitting and receiving telecommunication signals, that is, in the case of the WLL subscriber unit, the subscriber unit comprises a terminal equipment consisting of a radio part and a teleadapter, and a user interface, such as a telephone, a telefax terminal, a computer/modem combination or the like, connected to the terminal equipment.
Description of the Related Art
As a call departs from a subscriber unit of a known WLL system, a calling is first transmitted from the subscriber unit to the subscriber network element. The subscriber network element immediately acknowledges said calling by sending a standby message to the subscriber unit, after which it sends a signal indicating the OFF-hook state to a local exchange of the public switched telephone network. After this, diallings are transmitted from the subscriber unit, for instance as digit frames of said WLL system, and said diallings are converted in the subscriber network element into dialling signals used in the public switched telephone network. Subsequently, the subscriber network transmits the dialling it received to the local exchange that handles the digit analysis and the switching of the call as if it were a question of a normal wired subscriber unit of the public switched telephone network.
In the above-described known WLL system, problems occur in a situation in which an outgoing and a terminating call collide. The collision of calls means that a call (an outgoing call) is being set up from a subscriber unit at the same time as a calling, that is, in practice a call (a terminating call), is transmitted by the local exchange to the subscriber unit. Such a situation can occur, for example, if a calling signal intended for a certain subscriber unit is transmitted from the local exchange to the subscriber network element at the same time as a call is being set up from the subscriber unit in question. If the subscriber network element regardless of the terminating call sends an OFF-hook message to the exchange in order to forward the outgoing call to the exchange, the exchange interprets the outgoing call as a response to the terminating call, whereby the outgoing and terminating calls are connected into one call at the exchange. The diallings transmitted from the WLL subscriber unit will then be heard in the handset of the receiving party and the user of the WLL subscriber unit will have no way of noticing, at least not at an early stage, that the call has been switched incorrectly.
The above-mentioned situation occurs at l
REFERENCES:
patent: 5123042 (1992-06-01), Saegusa et al.
patent: 5303290 (1994-04-01), Redberg et al.
patent: 5381415 (1995-01-01), Mizutani
patent: 5577113 (1996-11-01), Bray et al.
Heikkila Vesa
Liinamaa Olli
Pentikainen Heimo
Rusi Pekka
Sarpola Jussi
Bost Dwayne D.
Nokia Telecommunications Oy
Wyche Myron K.
LandOfFree
Method for handling collision of calls does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for handling collision of calls, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for handling collision of calls will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2068993