Abstract: A hydraulic percussion device and method of controlling a working cycle of a percussion piston is provided. A rock breaking machine includes a percussion device provided with a reciprocating piston executing a working cycle. The operation is controlled by means of a control unit generating control signals for independently operable feed and discharge valves of a hydraulic system. The position of the piston is detected by a sensing device.

Abstract: A method of controlling the operation of a packet switched CDMA telecommunication network, wherein N network users are connected to the network by respective terminals, and the terminal of each user is assigned an orthogonal receiver code. To improve the properties of the packet network, the network terminal wanting to transmit senses the channel forming the transmission path for the presence of the receiver code of the other communicating party, i.e. the receiving terminal, in signals transmitted by the other terminals, the receiving terminal being the terminal to which the sensing terminal wants to transmit data in packet format. If the receiver code is not detected in the channel, the terminal wanting to transmit initiates the transmission of packet-format data encoded by the receiver code, whereas if the receiver code is detected in the channel, the terminal wanting to transmit remains waiting so as to repeat the above-described sensing algorithm after a period of time.

Abstract: A method of controlling the operation of a packet switched CDMA telecommunication network for controlling the operation of transmitters and receivers. The terminals of network users (U.sub.i,j) communicate with other terminals (U.sub.j,i) via a CDMA channel, and the terminal of each user is assigned a receiver code (r.sub.i,j) and a transmitter code (t.sub.i,j) used by the terminals for encoding packets to the other terminals of the network. To improve the performance of the network, the terminals sense the channel for the presence of the receiver codes (r.sub.i,j) and/or the transmitter codes (t.sub.i,j) at the different stages of the connection establishment, and the transmitting terminal (TER.sub.i) transmits encoded request packets (REQ) and data packets (DAT) to the channel on the basis of the sensing procedure, and the other communicating party, i.e. the receiving terminal (TER.sub.j), receives said encoded packets and transmits encoded acknowledgement packets (ACK) and busy tone packets to the channel.

Abstract: An optimization method for sidelobe suppression filters, and a filter utilizing a binary coding waveform are formulated. The method comprises expanding the frequency transfer function of an ideal sidelobe suppression filter into a polynomial series; truncating the polynomial series into a finite-termed polynomial series with unknown weighting coefficients A,B,C,D . . . , using the inverse Fourier transform to convert the finite-termed polynomial series into the corresponding pulse response in the time domain; then using the LP algorithm to minimize the output peak sidelobes to determine all the weighting coefficients A, B, C, D . . . and inserting them back to the inverse transfer function of the optimized filter.