Abstract: In packet switched data transfer of the cellular radio system, the control of the transmission power comprises characteristics as well of the closed-loop control and the open-loop control. Before forming the connection and during long pauses between the packets, the terminal device measures the control signal transmitted by the base station and compares its signal power (R0) to the target level (t0), that is included by the base station in the control signal as a parameter. The base station informs in the control signal also the transmission power, whereby the terminal device sets the same power to be its transmission power, corrected by the difference between the target level and the measured quality of the link (t0-R0). In addition, also the measured quality of the link (RXQUAL) is transmitted in the acknowledgment messages of the packets, whereby the transmitting device changes its transmission power so that the quality will be controlled to the certain target level.

Abstract: The object of the invention is a method for the encryption of information transferred between data transfer devices (MS, SGSN) in a data communication system wherein one or more data frames are created from one or more data packets formed from the information by the application. The data frames comprise at least a header field and a data field. In the method, at least some part of the data packets is ciphered by using a ciphering key (Kc). To the data frames, synchronization data (COUNT) is attached, the value of which is changed at least at the transmission of each data frame.

Abstract: A packet radio system encapsulates data packets of external data networks by a point-to-point protocol PPP (FIGS. 4A, 4B), and passes them through one or more sub-networks to a point which supports the protocol of the encapsulated data packet. In addition, a special radio link protocol of the packet radio network is required on the radio interface between a mobile data terminal equipment and a support node. PPP packets are encapsulated in data packets of said radio link protocol. The disadvantage of the arrangement is that the data packets of both the PPP protocol and the radio link protocol contain protocol-specific fields, which reduces the transmission capacity of user information. Therefore, a PPP packet is compressed (FIG. 4C) before the encapsulation (FIG. 4D) by removing therefrom the unnecessary control fields. After having been transferred over the radio interface, the PPP packet is decompresssed into its original format (FIGS. 4F, 4G).

Abstract: The invention relates to a method, device (MS, BTS, GSN) and telecommunication network for avoiding collisions in time divided two-way radio communication, in which messages are transmitted in a first communication direction in a first time slot and in a second opposite communication direction in a second time slot. In the method, device (MS, BTS, GSN) and telecommunication network according to the invention the first time slot in the first direction of communication is detected and, based upon the detection, such a time slot is selected for the second time slot which will not overlap the first time slot.

Abstract: A digital telecommunications system and method for non-transparent data transmission includes a non-transparent data connection between a transmitting party and a receiving party, on which channel coding is employed. The transmission buffer buffers the data frames to be transmitted and stores the transmitted data frames until it receives an acknowledgement of successful reception. This is avoided by monitoring the quality of the non-transparent connection, and if the quality of the the connection drops to a specific threshold value, by changing the channel coding scheme of the connection for a more efficient one. Simultaneously, however, more channel capacity is allocated for the connection in according with the chosen channel coding scheme so that the original nominal user data rate can be maintained unchanged or nearly unchanged.

Abstract: A location management method is provided for packet data transmission in a mobile communication system. To reduce the amount of signalling for location management concerning packet transmission compared to location management concerning normal traffic, location data of the mobile stations utilizing a data service is updated in a special data service user database. Packets to these mobile stations are sent via the cells as indicated by location data in that database. The database resides in a data service center which interfaces a data network.

Abstract: A method for continuous overall regulation of a former of a paper or board machine or equivalent in which a physical fluid flow model of the drainage and the flow state of the pulp suspension flow is formed. The model is solved by making use of the data on the geometry of the former and initial and boundary conditions necessary for a solution to the model. The difference between the simulated state, which has been obtained as the solution of the physical flow model, and the state adopted as the target is determined as the cost function, wherein the target state is determined by means of the quality requirements of the paper and possibly by means of the costs of operation and the runnability of the paper machine. The cost function is optimized and, thus, optimal regulation values and set values are obtained for the regulation devices and/or actuators of the former in view of the given cost function.

Abstract: A method for the continuous overall regulation of a single-layer or multi-layer headbox of a paper, board or pulp-draining machine. A physical fluid flow model of a pulp suspension flow discharged from the headbox to be regulated is formed and solved to obtain a simulated flow state based, e.g., on data on the geometry of the headbox and initial and boundary conditions related to the headbox. A target flow state based on the quality requirements of the paper produced from the pulp suspension flow and the costs of operation and runnability of the machine is obtained and a difference between the simulated flow state obtained as the solution of the flow model and the target flow state is determined. This difference constitutes a cost function which is optimized to determine optimal regulation values and set values for instrumentation devices and actuators of the headbox which affect the pulp suspension flow.

Abstract: For bidirectional transmission of packet data, a packet data service unit (Agent) is disposed in a digital cellular system connected to be in association with a Mobile Switching Center, and connecting the cellular network to the date network. As a mobile station is connected to the packet data service unit, signalling related to connection formation characteristics of the network is first accomplished. As a result thereof, the mobile station and the data service unit are provided with a number of stored parameters relating to each other. This situation creates or is called a virtual channel.

Abstract: The invention relates to a method for transmitting packet data in a cellular system. The number of time slots in a TDMA frame dedicated for packet transmission varies according to transmission needs and each logical channel consisting of corresponding time slots in consecutive TDMA frames is independent of the other logical channels. A data packet is encoded in an information channel frame consisting of N-1 information bursts, and between the frames there can be an acknowledge/retransmission request burst (ARQ) reporting that a received frame was error-free or requesting retransmission. Thus, the information channel consists of repeated sequences of N bursts. Also disclosed are the structure of a packet paging burst (PP), packet random access burst (PRA), packet access grant burst (PAG), acknowledge/retransmission request burst (ARQ) as well as the use of the bursts in starting and maintaining the transmission.

Abstract: The invention relates to a method aiming at dynamic division of the radio capacity in a TDMA system dynamically between packet radio service and circuit switched service. According to the invention, some basic number of time slots are reserved for packet radio service and the rest are reserved for circuit switched service. When the traffic requirement of packet radio service increases, information regarding this is obtained by means of a request from a mobile station or through traffic measurement at the base transceiver station. This information is used as a criterion in allocating more time slots to packet radio service.

Abstract: The invention relates to a system for transmitting packet data in the air interface of a digital cellular system based on TDMA, Time Division Multiple Access. The mobile terminated logical channels comprise information channels designated for transmitting information and control channels, which can be a fast paging (FP) channel and an acknowledgement (A) channel. The mobile originated logical channels comprise information channels designated for transmitting information and a reservation (R) channel, whereon the mobile station requests the system to reserve a connection for transmitting packet data. According to the invention, for the TDMA frames there is allocated a variable number of time slots for packet transmission, taking into account the symmetricity/asymmetricity of the packet transmission, as well as the total packet transmission demand of the cell.

Abstract: A radio telephone system comprising a transceiver unit and an external device, such as a handset, computer or telecopier, in wireless infrared signal communication with the transceiver unit. The information transmitted between the transceiver unit and the external device is transmitted as infrared digital pulses. The infrared pulses maybe transmitted in four digital time division multiplexed channels.