Abstract: Every entry of a flow table has the following fields: a source IP address; a destination IP address; a protocol number; an identification; a source port number; a destination port number; a payload type; and SSRC information. An RTP-judging unit judges, when IP packets having a characteristic of a RTP header have been inputted continuously for predetermined time, that each of the IP packets includes an RTP packet. A packet-classifying unit classifies an inputted IP packet according to a judgment result by the RTP-judging unit and a pre-defined packet-classifying-rule.

Abstract: A card device to be inserted into a slot of an electronic apparatus having an electronic apparatus ground and electrically connected to this electronic apparatus, including a single antenna provided on a carrier, a card ground which is disposed on the carrier and electrically connected to the antenna, and a switch for carrying out, at a high frequency, a connection/disconnection of the card ground to/from the electronic apparatus ground in a condition where this card device is inserted in the slot.

Abstract: To use high noise transmission lines, such as an electric wire, as the lines to transmit signals, it is imperative to reduce the level of signals. The present invention is provided with a sending signal generating means 10, which outputs converted data after converting an input signal into a plurality of carrier signals assuming values at such intervals on the axis of frequency that the frequencies may not interfere with each other. If an interfering noise with any one of the plurality of frequencies arises on the transmission line, removal of only a carrier of the noise frequency would leave the communication in a good condition.

Abstract: To use high noise transmission lines, such as an electric wire, as the lines to transmit signals, it is imperative to reduce the level of signals. The present invention is provided with a sending signal generating means 10, which outputs converted data after converting an input signal into a plurality of carrier signals assuming values at such intervals on the axis of frequency that the frequencies may not interfere with each other. If an interfering noise with any one of the plurality of frequencies arises on the transmission line, removal of only a carrier of the noise frequency would leave the communication in a good condition. Furthermore, better results can be hoped for if the respective carrier signals are so arranged as not to interfere with each other or so arranged to intersect orthogonally with each other not only on the axis of frequency but also on the axis of time.

Abstract: An antenna diversity communications device switches communications paths between a plurality of antennas to improve reception in a frequency diversity communications system. Antenna selection is done in response to measurement of the receiving condition of the selected antenna. A memory unit stores frequency difference information between the current channel and the next channel. When the frequency difference between the current channel and the next channel is small enough to predict good correlation between the channels, and if current receiving conditions are good, the current channel remains connected. When the frequency difference between the current channel and the next channel is large enough to predict poor correlation, or if the receiving conditions on the current channel are bad, one of the other channels is selected.

Abstract: A highly reliable and high-speed data transmission is made by using an FH or MFSK mode as suitably selected according to the usage of channels. When a reception signal is entered into a receiver through a transmission line, (i) a signal processing unit supplies the spectrum intensity values of carrier frequencies, (ii) a channel detection unit controls the phase of a time slot based on the spectrum intensity values, selects the MFSK or FH modulation mode, and supplies reception code data corresponding to detected carrier frequencies, and (iii) a decoder supplies reception information data based on the reception code data.

Abstract: A highly reliable and high-speed data transmission is made by using an FH or MFSK mode as suitably selected according to the usage of channels. When a reception signal is entered into a receiver through a transmission line, (i) a signal processing unit supplies the spectrum intensity values of carrier frequencies, (ii) a channel detection unit controls the phase of a time slot based on the spectrum intensity values, selects the MFSK or FH modulation mode, and supplies reception code data corresponding to detected carrier frequencies, and (iii) a decoder supplies reception information data based on the reception code data.

Abstract: A highly reliable and high-speed data transmission is made by using an FH or MFSK mode as suitably selected according to the usage of channels. When a reception signal is entered into a receiver through a transmission line, (i) a signal processing unit supplies the spectrum intensity values of carrier frequencies, (ii) a channel detection unit controls the phase of a time slot based on the spectrum intensity values, selects the MFSK or FH modulation mode, and supplies reception code data corresponding to detected carrier frequencies, and (iii) a decoder supplies reception information data based on the reception code data.

Abstract: A highly reliable and high-speed data transmission is made by using an FH or MFSK mode as suitably selected according to the usage of channels. When a reception signal is entered into a receiver through a transmission line, (i) a signal processing unit supplies the spectrum intensity values of carrier frequencies, (ii) a channel detection unit controls the phase of a time slot based on the spectrum intensity values, selects the MFSK or FH modulation mode, and supplies reception code data corresponding to detected carrier frequencies, and (iii) a decoder supplies reception information data based on the reception code data.

Abstract: A highly reliable and high-speed data transmission is made by using an FH or MFSK mode as suitably selected according to the usage of channels. When a reception signal is entered into a receiver through a transmission line, (i) a signal processing unit supplies the spectrum intensity values of carrier frequencies, (ii) a channel detection unit controls the phase of a time slot based on the spectrum intensity values, selects the MFSK or FH modulation mode, and supplies reception code data corresponding to detected carrier frequencies, and (iii) a decoder supplies reception information data based on the reception code data.

Abstract: A magnetic recording device includes a magnetic disk drive for recording desired information as a magnetic signal and a reproducing signal amplifier for amplifying a small electric signal obtained by converting the magnetic signal. The reproducing signal amplifier includes an amplifier for amplifying a small electric signal supplied through an input terminal into an amplified signal having an appropriate amplitude, a central value detection circuit for detecting a central value of the AC component of the amplified signal output by the amplifier and outputting a central value signal consisting of the DC component of the amplified signal, and a subtracter for obtaining a difference between the amplified signal and the central value signal and outputting a reproducing signal.

Abstract: An amplifier circuit for amplifying a change in a resistance value of a magnetic resistance element is formed by connecting a first and a second current mirror circuits having the same structure in cascode, so that a voltage change is amplified without using a capacitive coupling. Hence, a high-pass filter is not created as a parasitic circuit, whereby a gain is maintained high in the low frequency region and a low frequency characteristic is excellent. Further, since control electrodes of transistors which form each current mirror circuit are grounded through the capacitance, a noise is reduced without using a conventional feedback circuit. This eliminates an influence of the feedback circuit over a high frequency characteristic, and therefore, a high frequency characteristic becomes excellent.