Abstract: A present invention provides a spread spectrum communication apparatus that acquisition of synchronization of the pilot signal can be conducted in a short time with a high probability when a mobile station stays in the same radio area or in its vicinity. The spread spectrum communication apparatus includes a PN period holding counter is provided in a search receiver, and phase information of the PN code is held in the counter during the power off interval. At the time of operation of synchronization acquisition of a pilot signal conducted when power is turned on again, the operation of synchronization acquisition of the pilot signal is conducted with a preset search width around the phase derived on the basis of the above described held phase information.

Abstract: There is provided a mobile radio communication device which is designed to prevent dishonest applications by using a management table (30) for storing a plurality of MINs and count values as authentication parameters corresponding to the MINs and effecting the authentication procedure at the time of radio connection to a base station. Whether or not an input MIN is already set in the management table (30) is determined at the time of MIN setting operation, and if it is already set, it is determined that the setting operation is a resetting operation and the already set MIN and count value are kept held as they are. On the other hand, if the input MIN is not set in the management table (30), whether or not a MIN having a count value of "0" is set in the management table (30) is determined, and if it is set, an input MIN is set in place of the above MIN, and if it is not set, an input MIN and the initial value "0" of the count value are set in an available area of the management table (30).

Abstract: In a mobile station apparatus of this invention, when a first offset is captured by a search operation performed by a first PN code search mode, it is checked, on the basis of the SID broadcasted from the corresponding base station through a sync channel, whether a base station of a desired carrier is captured. If a base station of an undesired carrier is captured, a second PN code search mode receives a neighbor list message broadcasted from the base station of the undesired carrier through a paging channel, and causes a search receiver to perform a search operation, excluding spreading code offsets notified by the message.

Abstract: When at a starting time of an apparatus with a power supply turned ON a designation operation of a communication mode is carried out or one communication operation is finished, a base station search control section (21) in a control circuit (20) conducts a search on control channels received from respective base station, selects from among those base stations whose control channels are received at an electric field strength greater than a predetermined level a base station possessing a desired communication mode and having the greatest electric field strength, and acquires and sets this base station, thus effecting a transfer to a standby state.

Abstract: Disclosed is a mobile radio communication apparatus having a sync restoring control function equipped in a controller. When disconnection of reception is detected during communication, the sync restoring control function sends a sync acknowledge indicate signal to a digital demodulator within a cutoff allowance period to re-establish synchronized reception. The bit error rate is detected during communication, and a BER code indicating this bit error rate is displayed on a display.

Abstract: A radio communication apparatus of this invention includes a mode designation switch for selectively designating and inputting a desired mode from an analog mode and a digital mode, and a mode storage circuit for storing the desired mode designated and input by the mode designation switch and has a mode setting control function, a mode comparison function, and a mode change control function. In order to establish a radio link, control is performed to set a mode for transmitting a communication signal in accordance with the desired mode stored in the mode storage circuit. After the start of transmission of the communication signal, the mode comparison function compares the mode set by the mode setting control function with the desired mode stored in the mode storage circuit.

Abstract: A mobile radio communication apparatus includes a common channel detecting unit which judges whether or not a paging channel and an access channel which are assigned to one base station are common based on a predetermined parameter (CPA) which is transmitted from the base stations. If the CPA indicated a predetermined value indicating that the paging channel and the access channel are common channel, then a memory stores that information representing the base station which transmits the strongest level of all the received access channel at an input of a receiver of the mobile radio communication apparatus.

Abstract: A radio communication apparatus of this invention includes a mode designation switch for selectively designating and inputting a desired mode from an analog mode and a digital mode, and a mode storage circuit for storing the desired mode designated and input by the mode designation switch and has a mode setting control function, a mode comparison function, and a mode change control function. In order to establish a radio link, control is performed to set a mode for transmitting a communication signal in accordance with the desired mode stored in the mode storage circuit. After the start of transmission of the communication signal, the mode comparison function compares the mode set by the mode setting control function with the desired mode stored in the mode storage circuit.

Abstract: A radio communication apparatus for use in a time division multiple access (TDMA) communication system prevents signals from being transmitted through a transmitter in response to recognition that the transmitter operates during an unassigned time slot. A controller is utilized to recognize that the transmitter operates during the unassigned time slot. Power to the transmitter is disconnected in response to the recognition.

Abstract: When remote control data has been input during calling in analog mode, a mobile radio communication apparatus according to the invention outputs a predetermined first voice frequency signal indicative of the remote control data and transmitting the signal to a radio link, and outputs the first voice frequency signal. Further, when remote control data has been input during calling in digital mode, the mobile radio communication apparatus outputs message data indicative of the remote control data and transmitting the message data to a radio link, generates a second voice frequency signal corresponding to the input remote control data and also the first voice frequency signal, and outputs the second voice frequency signal before the message data is transmitted.

Abstract: A dual mode cellular radio communication apparatus having a received signal strength measuring function is disclosed. The measured strength of the signal may be corrected when the apparatus operates in the digital mode. The value of corrected strength may be used for indicating the received signal strength to a user of the apparatus and for reporting the received signal strength to a base station. Similarly, the measured strength of the signal may be corrected for indicating the received signal strength to a user of the apparatus when the apparatus operates in the analog mode.

Abstract: A tone signal is formed by repeatedly reading out digital data stored in a memory device. Thus a predetermined tone wavefrom signal is stored in the memory device as data corresponding to the amplitude value at a plurality of sampling points and the data are repeatedly read out at a predetermined speed. A quasi sine wave signal is formed based on the read out signal. Harmonic components are eliminated from the quasi sine wave signal with a lowpass filter, thereby forming a desired tone signal.