Portable radio transceiver system having improved adaptor and/or improved receiver signal control arrangement

• US 5,261,121 A
• Filed: 08/13/1990
• Issued: 11/09/1993
• Est. Priority Date: 08/11/1989
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Hashimoto, Kazuya
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): URBAN, EDWARD F
• Application Number:
  US07/566,672
• Time in Patent Office: 1,184 Days
• Field of Search: 455/89, 455/90, 455/127, 455/343, 455/277, 455/277.1, 455/277.2, 455/272, 455/275, 455/289
• US Class Current: 455/550.1
• CPC Class Codes: H04B 1/3877 Arrangements for enabling portable transceivers to be used in a fixed position, e.g. cradles or boosters
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence
• CPC Class Codes: H04B 7/0825 with main and with auxiliary or diversity antennas

Abstract

In order to enable a diversity reception in a portable radiotelephone without detrimentally increasing the size and weight thereof, an adaptor to which diversity antennas are coupled and into which the radiotelephone is inserted in an in-car mode, is provided with a diversity switch and a diversity switch controller. The portable radiotelephone is arranged to switch over from its own antenna to the diversity antennas upon insertion into the adaptor. The portable radiotelephone is further provided with an arrangement for exhibiting a correct receive signal strength irrespective of the fact it is set in the adaptor or used in a portable mode.

Claims

1. A portable radio-transceiver system comprising:

a portable radio transceiver means for sending and receiving information;

means comprising diversity antennas for simultaneously sending and receiving two radio signals at slightly different frequencies, said diversity antennas being fixable to a vehicle;

an adaptor for mounting in the vehicle for removably receiving said portable radio transceiver, said adaptor being coupled to said diversity antennas,

said adaptor including;

diversity switch means which is coupled to said diversity antennas and selects one of said diversity antennas and outputs a first signal to said portable radio transceiver; and

switch control means which is coupled to said diversity switch means and receives a second signal from said portable radio transceiver indicative of the strength of said first signal, said switch control means outputting a third signal if a level of said second signal falls below a predetermined level, said third signal being applied to said diversity switch means for controlling the switching thereof.

2. A portable radio transceiver system as claimed in claim 1, wherein said portable transceiver means comprises:

control signal generating means for outputting a control signal which takes a control level in response to an attachment of said portable radio transceiver to said adaptor; and

first switch means, which is coupled to said control signal generating means, for switching from an antenna coupled to said portable transceiver to a coupling for said diversity antennas in response to said control signal.

3. A portable radio transceiver system as claimed in claim 2, wherein said portable transceiver means further comprises:

second switch means for switching from a battery installed therein to a vehicle mounted battery which is coupled to said adaptor in response to said control signal;

a first signal generator for outputting a first reference signal;

a second signal generator for outputting a second reference signal, said second reference signal having a level which is lower than a level of said first reference signal;

third switch means for switching between said first and second signal generators in response to said control signal; and

a comparator coupled to receive one of said first and second reference signals via said third switch means, said comparator comparing said second signal with one of said first and second reference signal.

4. A portable radio transceiver system comprising:

a portable radio transceiver for sending and receiving information;

means comprising diversity antennas for simultaneously sending and receiving two radio signals at slightly different frequencies, said diversity antennas being fixable to a vehicle;

an adaptor for mounting in the vehicle for removably receiving said portable radio transceiver, said adaptor being coupled to said diversity antennas,

said adaptor including;

diversity switch means which is coupled to diversity antennas and selects one of said diversity antennas and outputs a first signal to said portable radio transceiver;

switch control means which is coupled to said diversity switch means, said switch control means receiving a second signal from said portable radio transceiver which is indicative of the strength of said first signal and outputting a third signal if a level of said second signal falls below a predetermined level, said third signal being applied to said diversity switch means and controlling the switching thereof;

control signal generating means for outputting a control signal which takes a control level in response to an attachment of said portable radio transceiver to said adaptor; and

first switch means, which is coupled to said control signal generating means, for switching from an antenna coupled to said portable transceiver to said diversity antennas in response to said control signal.

5. A portable radio transceiver system as claimed in claim 4, wherein said portable transceiver further comprises:

second switch means for switching from a battery installed therein to a vehicle mounted battery coupled to said adaptor in response to said control signal;

a second signal generator for outputting a second reference signal, said second reference signal having a level which is lower than a level of said first reference signal;

third switch means for switching between said first and second signal generators in response to said control signal; and

a comparator which is coupled to receive one of said first and second reference signals via said third switch, said comparator comparing said second signal with said one of said first and second reference signals.

6. A portable radio transceiver system comprising:

a portable radio transceiver for sending and receiving information;

means comprising diversity antennas for simultaneously sending and receiving two radio signals at slightly different frequencies, said diversity antennas being fixable to a vehicle;

an adaptor for mounting in the vehicle for removably receiving said portable radio transceiver, said adaptor being coupled to said diversity antennas,

said adaptor including;

diversity switch means which is coupled to said diversity antennas and selects one of said diversity antennas and outputs a first signal to said portable radio transceiver;

switch control means which is coupled to said diversity switch means, said switch control means receiving a second signal from said portable radio transceiver which is indicative of the strength of said first signal and outputting a third signal if a level of said second signal falls below a predetermined level, said third signal being applied to said diversity switch means and controlling the switching thereof;

control signal generating means for outputting a control signal which takes a control level in response to an attachment of said portable radio transceiver to said adaptor;

first switch means, which is coupled to said control signal generating means, for switching from an antenna coupled to said portable transceiver to said diversity antennas in response to said control signal

second switch means for switching from a battery installed therein to a vehicle mounted battery coupled to said adaptor in response to said control signal;

a first signal generator for outputting a first reference signal;

a second signal generator for outputting a second reference signal, said second reference signal having a level which is lower than a level of said first reference signal;

third switch means for switching between said first and second signal generators in response to said control signal; and

a comparator which is coupled to receive one of said first and second reference signals via said third switch, said comparator comparing said second signal with said one of said first and second reference signals.