Dual mode radio communication apparatus having function of selectively designating analog or digital mode

• US 5,710,986 A
• Filed: 03/15/1996
• Issued: 01/20/1998
• Est. Priority Date: 02/05/1992
• Status: Expired due to Term

• Current Assignee: Fujitsu Mobile Communications Limited (Fujitsu Limited)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Haga, Takumi, Wakabayashi, Naoyuki, Sakagawa, Takashi, Obayashi, Arata
• Primary Examiner(s): Pham, Chi H.
• Application Number:
  US08/617,942
• Time in Patent Office: 676 Days
• Field of Search: 455/33.1, 455/33.2, 455/54.1, 455/54.2, 455/73, 455/78, 455/89, 379/58-60, 379/63, 375/216
• US Class Current: 455/553.1
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

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. If these modes are determined not to coincide with each other by the mode comparison function, control is performed to change the mode set by the mode setting control function to the desired mode stored in the mode storage circuit in accordance with the mode change control function.

Claims

1. A radio communication apparatus used in a dual mode cellular radio system for selectively transmitting a communication signal in an analog or digital mode through a radio link established between a base station and said radio communication apparatus, comprising:

mode designation input means for selectively designating and inputting a desired mode from the analog mode and the digital mode;

mode comparison means for comparing the desired mode with the mode currently used in transmission of the communication signal when said mode designation input means designates and inputs the desired mode during the transmission of the communication signal; and

change control means for transmitting to the base station a mode change request signal for changing the mode currently used in the transmission of the communication signal into the desired mode when said mode comparison means detects that the mode currently used in the transmission of the communication signal does not coincide with the desired mode, and for inhibiting the mode change request signal from being transmitted to the base station when said mode comparison means detects that the mode currently used in the transmission of the communication signal coincides with the desired mode.

2. The radio communication apparatus according to claim 1, wherein said change control means transmits to the base station at least the mode change request signal when said mode comparison means detects that the mode currently used in the transmission of the communication signal does not coincide with the desired mode, and inhibits at least the mode change request signal from being transmitted to the base station when said mode comparison means detects that the mode currently used in the transmission of the communication signal coincides with the desired mode.

3. The radio communication apparatus according to claim 1, wherein said mode comparison means and said change control means respectively execute mode comparison processing and control processing of mode change control prior to a start of main control associated with the mode change.

4. A dual mode cellular radio telephone apparatus used in a cellular radio system wherein speech signals are selectively communicated with a base station in either one of an analog transmission mode or a digital transmission mode over one or more radio channels and the speech signals are selectively subject to a digital signal processing for a secret communication, comprising:

establishing means for establishing a speech communication with the base station over a radio link on the basis of a transmission mode designated by the base station;

first user-actuatable switch means for selectively requesting the analog transmission mode and the digital transmission mode;

first transmitting means for transmitting a mode designation signal for requesting the analog transmission mode when the analog transmission mode is requested by said first user-actuatable switch means and for transmitting a mode designation signal requesting the digital transmission mode when the digital transmission mode is requested by said first user-actuatable switch means;

second user-actuatable switch means for requesting the secret communication;

second transmitting means responsive to an actuation of the second user-actuatable switch means for transmitting the mode designation signal requesting the digital transmission mode over the radio link;

determining means for determining whether the radio link is established between said dual mode cellular radio telephone apparatus and said base station in the digital transmission mode after the mode designation signal requesting the digital transmission mode is transmitted by said second transmitting means; and

informing means for informing a speaker of capability of the secret communication when said determining means determines that the radio link is established in the digital transmission mode, and for informing the speaker of incapability of the secret communication when said determining means determines that the radio link is not established in the digital transmission mode.

5. A radio communication apparatus used in a dual mode cellular radio system for selectively transmitting a communication signal in an analog or digital mode through a radio link established between a base station and said radio communication apparatus, comprising:

a mode designation input apparatus for selectively designating and inputting a desired mode from the analog mode and the digital mode;

a mode comparison circuit for comparing the desired mode with the mode currently used in transmission of the communication signal when said mode designation input apparatus designates and inputs the desired mode during the transmission of the communication signal; and

a change control circuit for transmitting to said base station a mode change request signal for changing the mode currently used in the transmission of the communication signal into the desired mode when said mode comparison circuit detects that the mode currently used in the transmission of the communication signal does not coincide with the desired mode, and for inhibiting the mode change request signal from being transmitted to said base station when said mode comparison circuit detects that the mode currently used in the transmission of the communication signal coincides with the desired mode.

6. The radio communication apparatus according to claim 5, wherein said change control circuit transmits to said base station at least the mode change request signal when said mode comparison circuit detects that the mode currently used in the transmission of the communication signal does not coincide with the desired mode, and inhibits at least the mode change request signal from being transmitted to said base station when said mode comparison circuit detects that the mode currently used in the transmission of the communication signal coincides with the desired mode.

7. The radio communication apparatus according to claim 5, wherein said mode comparison circuit and said change control circuit respectively execute mode comparison processing and control processing of mode change control prior to a start of main control associated with the mode change.

8. A dual mode cellular radio telephone apparatus used in a cellular radio system wherein speech signals are selectively communicated with a base station in either one of an analog transmission mode or a digital transmission mode over one or more radio channels and the speech signals are selectively subject to a digital signal processing for a secret communication, comprising:

communication circuitry for establishing a speech communication with said base station over a radio link on the basis of a transmission mode designated by said base station;

a first user-actuatable switch for selectively requesting the analog transmission mode and the digital transmission mode;

a first transmitter for transmitting a mode designation signal for requesting the analog transmission mode when the analog transmission mode is requested by said first user-actuatable switch and for transmitting a mode designation signal requesting the digital transmission mode when the digital transmission mode is requested by said first user-actuatable switch;

a second user-actuatable switch for requesting the secret communication;

a second transmitter responsive to an actuation of the second user-actuatable switch for transmitting the mode designation signal requesting the digital transmission mode over the radio link;

a controller for controlling said communication circuitry and for determining whether the radio link is established between said dual mode cellular radio telephone apparatus and said base station in the digital transmission mode after the mode designation signal requesting the digital transmission mode is transmitted by said second transmitter; and

a display for informing a speaker that the secret communication is enabled when said controller determines that the radio link is established in the digital transmission mode, and for informing the speaker that the secret communication is not enabled when said controller determines that the radio link is not established in the digital transmission mode.