Telecommunications – Receiver or analog modulated signal frequency converter – With particular receiver circuit
Reexamination Certificate
1997-12-23
2001-07-17
Vo, Nguyen T. (Department: 2682)
Telecommunications
Receiver or analog modulated signal frequency converter
With particular receiver circuit
C455S574000, C455S039000
Reexamination Certificate
active
06263200
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a radio (wireless) terminal apparatus such as a mobile vehicle telephone and a portable telephone, and a mobile communication system such as a mobile (vehicle) telephone system and a portable telephone system with employment of this radio terminal apparatus. More specifically, the present invention is directed to battery power saving techniques under call waiting states of radio terminal apparatuses for constituting this sort of mobile communication system.
2. Description of the Related Art
In general, a radio (wireless) terminal apparatus for constructing a mobile communication system performs a location registering operation when a power supply is turned ON, and thereafter operation of this radio terminal apparatus is brought into a call waiting state. Then, under this call waiting state, a battery power saving operation is carried out.
As such a conventional radio terminal apparatus, for instance, Japanese Laid-open Patent Disclosure JP-A-Showa 63-316942 opened in 1988 discloses “RADIO TELEPHONE APPARATUS”. It should be noted that the disclosed radio telephone apparatus will be referred as “first conventional technique” hereinafter in this specification. Referring now to
FIG. 1A
, FIG.
1
B and
FIG. 2A
to
FIG. 2D
, a description will now be made of this radio terminal apparatus related to the first conventional technique.
FIG. 1A
schematically represents the arrangement of the mobile communication system according to the first conventional technique. This mobile communication system is arranged by a radio (wireless) base station control apparatus, a plurality of radio base station apparatuses, and a plurality of radio (wireless) terminal apparatuses.
FIG. 1B
is a block diagram for showing the arrangement of the radio terminal apparatus for constituting this conventional mobile communication system. This radio terminal apparatus is arranged by a radio (wireless) signal transmitting/receiving unit
1
, a speaker
2
, a microphone
3
, an input/output apparatus
4
, a control unit
5
, a memory unit
6
, and an antenna
9
. A detailed description of each of these elements will be explained in connection with a preferred embodiment.
FIG. 2A
to
FIG. 2D
are explanatory diagrams for explaining the summary of battery power saving operation executed in the radio terminal apparatus of the first conventional technique. More specifically,
FIG. 2A
is a timing chart for representing a notification signal group transmitted from the radio base station control apparatus via the radio base station.
FIG. 2B
is a timing chart for showing an ON/OFF condition of the power supply supplied to the radio signal transmitting/receiving unit
1
(simply referred to as a “signal receiving circuit”) of the radio terminal apparatus.
FIG. 2C
is another timing chart for showing the above-described notification signal group, in which the scale of the abscissa in
FIG. 2A
is reduced.
FIG. 2D
is another timing chart for representing the above-described ON/OFF condition, in which the scale of the abscissa in
FIG. 2B
is reduced at the same reduction ratio of FIG.
2
C.
Under call waiting state of the radio terminal apparatus, the turn-ON/OFF operation of the power supply of the signal receiving circuit is controlled in a predetermined time period (this time period is referred as the “battery power saving period”). As shown in
FIG. 2B
, within
1
battery power saving period, the power supply of the signal receiving circuit is turned ON in a ¼ section of 1 time period, whereas this power supply is turned OFF in a ¾ section of 1 time period. In other words, a ratio of the turn ON/OFF of the power supply of the signal receiving circuit is 1:3. Then, while the power supply of the signal receiving circuit is turned ON, a confirmation is made as to whether or not the call signal to the own radio terminal apparatus is produced. This call signal contains the notification signal and the calling signal (will be explained later).
As shown in
FIG. 2C
, the radio base station control apparatus transmits the notification signal group to the radio terminal apparatus via the radio base station apparatus, for instance, at an interval of 5 minutes in order to register the location. This notification signal group is constituted by a plurality of notification signals identical to each other, and these notification signals are transmitted in the asynchronous mode within the above-described battery power saving period. Also, a total number of notification signals contained in the notification signal group is determined in order that the transmission time of the notification signal group becomes longer than the battery power saving period. Such a notification signal overflowed from the battery power saving period is called as a “notification signal of +a&agr;”. As represented in
FIG. 2A
, in this first conventional technique, 4 pieces of the notification signals are transmitted within 1 battery power saving period, and further one piece of the notification signal is transmitted as the “notification signal of +&agr;”. In other words, the radio base station control apparatus transmits 5 pieces of the continuous notification signals via the radio base station apparatus in the interval of 5 minutes.
As indicated in
FIG. 2B
, in the radio terminal apparatus, the power supply of the signal receiving circuit is turned ON under control of the control unit in the ¼ section of the battery power saving period. As previously explained, the timing when this power supply is turned ON is not synchronized with the notification signal sent from the radio base station control apparatus via the radio base station apparatus.
It should be understood that when a call is issued to the radio terminal apparatus managed by the radio base station control apparatus, this radio base station control apparatus transmits the calling signal group via the radio base station apparatus irrelevant to the above-described transmission timing of the notification signal group, as shown in FIG.
2
C. Similar to the above-described notification signal group, this calling signal group is constructed of 5 pieces of continuous calling signals (not shown).
The reason why either the same notification signals or the same calling signals are continuously transmitted 5 times in this first conventional technique is given as follows. That is, the power supply of the signal receiving circuit is turned ON only in the ¼ section of the battery power saving period and further the battery power saving period is not synchronized with the send timing of either the notification signal group or the calling signal group. Thus, in order to firmly receive either the notification signal or the calling signal while the power supply of the signal receiving circuit is turned ON, either one piece of the notification signal or one piece of the calling signal is outputted in addition to either four pieces of the notification signals or four pieces of the calling signals, which correspond to the battery power saving period.
The battery power saving ratio is 75% in the case that the radio terminal apparatus of the first conventional technique is operated under call waiting state. Assuming now that the ON/OFF ratio of the power supply of the signal receiving circuit is 1:4, the battery power saving ratio is increased to 80% when this radio terminal apparatus is operated under call waiting state. However, in this case, either the same notification signals or the same calling signals are required to be continuously transmitted 6 times, so that the load given to the radio base station control apparatus is increased.
Another conventional radio terminal apparatus is disclosed in “JTC (AIR)/95.06.08-033R3 [SP-3418]”, section 6.4.1 “Alerting Protocol” on pages 69-74. This disclosed convention radio terminal apparatus is called as “second conventional technique”.
FIG. 3A
to
FIG. 3F
are explanatory diagrams for explaining the summary of battery po
Foley & Lardner
NEC Corporation
Ramos-Feliciano Eliseo
Vo Nguyen T.
LandOfFree
Radio terminal apparatus equipped with battery power saving... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Radio terminal apparatus equipped with battery power saving..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio terminal apparatus equipped with battery power saving... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2556642