摘要:
The invention relates to a procedure for ensuring emergency calls in a wireless local loop environment which is based on technology employed in a mobile telephone system and which comprises a telephone exchange (1), an access node (2) connected to the telephone exchange, a terminal device (3) and a base station (4) connected to the telephone exchange via the access node and serving to transmit call signals between the access node and the terminal device, in which the home network (5) of the terminal device is defined by the base station and the associated access node and in which base stations (7) of other networks are disposed in the environment of the local loop, so that the terminal device receives information signals from the surrounding base stations and, based on said information signals, determines the base station it is communicating with, and the emergency call is set up via any base station compatible with the terminal device. To ensure successful set-up of an emergency call when connection between the terminal device (3) and the telephone exchange (1) of its home network (5) is lost, a dial tone is generated by means of the terminal device, an emergency number dialed via the terminal device is identified and the emergency call function of the mobile telephone system is used for the set-up of the emergency call.
摘要:
The present invention relates to a method for establishing a telecommunication connection from a subscriber station (1, 9) of a radio system forming a wireless subscriber connection to a public switched telephone network (PSTN), in which method a call request is received from the subscriber station. For achieving a faster and simpler connection establishment than heretofore, a traffic channel is reserved from a data transfer channel (12) leading to the PSTN exchange (7) to be used by the subscriber station (1) that has sent a call request, a connection is established to the PSTN exchange (7), an acknowledgement message is sent to the subscriber station (1), and a speech path is connected between the PSTN exchange (7) and the user interface (2) of the subscriber station, whereby the sound signals fed by the PSTN exchange (7) are transmitted directly on the speech path to the user interface (2) of the subscriber station (1), and the diallings supplied from the user interface (2) of the subscriber station are transmitted to the PSTN exchange (7).
摘要:
The invention describes serving, on application level, services between IP networks supporting addresses which require translation, wherein a service is processed between a common address space common to IP networks and a specific address space specific to an IP network via a first interface which is accessible from the specific address space and a second interface which is accessible from the common address space.
摘要:
The invention relates to a method for transmitting a television data stream via a wireless network connection. The method comprises receiving at least one television data stream via the User Datagram Protocol (UDP); converting the at least one UDP television data stream into a Transmission Control Protocol (TCP) data stream; and transmitting the TCP data stream via the wireless network connection over a point-to-point link.
摘要:
The invention relates to a method for ensuring the adequacy of transmission capacity in a digital packet-switched cellular network where both voice sample packets and associated header fields are transmitted in real time in one and the same transmission channel. The invention also relates to a terminal employing the method. In the method, the contents of voice sample packets at the beginning of a speech spurt are partly replaced by packet header field data in situations where the combined bit count of voice sample data and packet header data exceeds the transmission capacity of the transmission channel.
摘要:
A method of multiplexing different sessions using the same authorized contexts for media, comprising: distinguishing the sessions to be multiplexed, by a device; creating a new session on a control plane; indicating media flows of different sessions; and enabling the sessions to share the same authorized context for media, thus being multiplexed.
摘要:
A packet mode (e.g. IP) communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the communication layer comprises a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run packet mode communication service applications, which communicate with packet mode communication service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of communications. Embedded user-plane signaling is used for connecting call parties for a packet mode speech two-party (one-to-one) communication. Embedded signaling in the user-plane's bearer makes it unnecessary to reserve another bearer for the control plane's signaling, which saves network resources and allows to achieve a short connection setup time.
摘要:
A power detector for detecting the magnitude of a radio frequency (RF) signal comprises a detector transistor (V1) which provides an output signal (DC-OUT) in dependence upon the input RF signal. The detector transistor is biased with a biasing circuit which comprises two transistors (V2,V3) in a feedback loop coupled to the base of the detector transistor (V1). The detector can be used as both current and voltage amplifier. One of the transistors (V3) in the feedback loop provides temperature compensation.
摘要:
A radio frequency transmission circuit comprising a first signal generating means and a second signal generating means, means for modulating one of the first and second signals to produce a modulated signal, and mixer means to combine the other of the first and second signals and the modulated signal to produce an RF output signal. The first signal is controlled by a feed back loop comprising a second mixer having an input from both the first and second signals, whereby fluctuations in the frequency of the second signal are compensated for by adjustment of the first signal so as to maintain the RF output signal at a substantially constant frequency.
摘要:
By the method according to the invention, microphony, i.e. interference voltages caused by vibration, in a circuit including ceramic surface-mounted capacitors is reduced by eliminating the direct-voltage differential (V1 - V2) effective across the capacitors (C30 - C36). The invention also relates to circuit arrangements implementing the method, and it can be advantageously applied to a radio telephone.