Telecommunications – Transmitter and receiver at separate stations – Plural transmitters or receivers
Reexamination Certificate
1998-12-23
2001-05-08
Kuntz, Curtis (Department: 2643)
Telecommunications
Transmitter and receiver at separate stations
Plural transmitters or receivers
C455S063300, C455S069000, C455S126000, C455S127500, C455S450000, C455S464000, C455S509000, C455S513000
Reexamination Certificate
active
06230022
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a transmitting method and apparatus, a sending power controlling method, and more particularly, suitably applied to a cellular radio communication system.
2. Description of the Related Art
In a cellular radio communication system, areas for offering communication service are divided into cells that have the desired size; a transmitting apparatus is placed in each cell as a fixed station. A communication terminal unit, that is a mobile station, will communicate with such a transmitting apparatus that is in the best status to communicate.
By the way, such a cellular radio communication system, when the desired communication is to be performed, may have the case where the transmission must be performed with a large sending power and the case where the lower sending power is enough to communicate, depending on the position of the mobile station. Therefore, in the cellular radio communication system, a transmitting apparatus and a communication terminal unit are monitoring a received power of each other, and they mutually notify power controlling information based on the result of the monitoring, so as to form a feedback loop and to perform sending-power controlling wherein the communication is achieved with the minimum sending power that is needed. Thus, the cellular radio communication system makes it possible to communicate efficiently with the minimum sending power and to reduce the consumption power in comparison with the case of fixed-power communication, so that such an effect can be obtained that the life time of the battery of a communication terminal unit can be elongated.
In such the cellular radio communication system, it is able to suppress excess sending power by performing transmission on the basis of the power controlling information that is informed from the partner of the communication, however, it is not able to maintain communication continuously by merely controlling the sending power on the basis of the power controlling information.
For instance, it is supposed that a transmitting apparatus
1
is communicating with communication terminal units
2
A to
2
D existing within the base station's own cell, wherein the transmitting apparatus
1
is communicating with the communication terminal unit
2
A using a down channel f
1
, communicating with the communication terminal unit
2
B using a down channel f
2
, communicating with the communication terminal unit
2
C using a down channel f
3
, and communicating with the communication terminal unit
2
D using a down channel f
5
, as shown in FIG.
1
. Besides, it is assumed that the communication terminal units
2
A,
2
C and
2
D are relatively distant from the transmitting apparatus
1
, and the communication terminal unit
2
B is relatively near to the transmitting apparatus
1
.
If sending power controlling is performed under such a situation, the transmitting apparatus
1
transmits transmission signals having relatively large sending power to the communication terminal units
2
A,
2
C and
2
D, and transmits a transmission signal having relatively small sending power to the communication terminal unit
2
B. This is because the signal power that are received by the communication terminal units
2
A,
2
C and
2
D are diminished relatively, since signal loss on the transmission line is in proportion to the distance. Therefore, under such a situation, the communication terminal units
2
A,
2
C and
2
D notify the power controlling information of increasing the sending power to the transmitting apparatus
1
; as a result, the transmitting apparatus
1
performs transmission to the communication terminal units
2
A,
2
C and
2
D, with a relatively large sending power.
FIG. 2
shows the situation of the sending power of this instance. As shown in the
FIG. 2
, the transmitting apparatus
1
transmits the transmission signals S
1
, S
3
and S
5
of the down channels f
1
, f
3
and f
5
that are used for communication with the communication terminal units
2
A,
2
C and
2
D with the large sending power, and transmits the transmission signal S
2
of the down channel f
2
that is used for communication with the communication terminal unit
2
B with the small sending power.
By the way, when a transmission signal is transmitted from a transmitting apparatus
1
, usually, the transmission signal is filtered to limit its band width, so that the signal is not transmitted to other channels than the allocated channel. For instance, the band of the transmission signal S
1
, which is transmitted through the down channel f
1
, is limited such that it falls within the band of the channel f
1
. However, it is not possible to completely limit the band by the filter in practice, and some signal components that leak into the adjacent channels exist. This leakage of signal components into adjacent channels is an unavoidable problem, because it is difficult to manufacture a filter that is able to completely cut off such out-of-band signal components.
In fact, in the situation shown in
FIG. 2
, the transmission signal S
1
that is transmitted through the down channel f
1
is leaking, in part, into the adjacent channels f
0
and f
2
, and the transmission signal S
3
that is transmitted through the down channel f
3
is also leaking, in part, into the adjacent channels f
2
and f
4
. If the adjacent channels are not being used or the electric power of the transmission signals that are transmitted through the adjacent channels are large, the signal components that leak into the adjacent channels offer no problem; however, if the power of the transmission signals that are transmitted through the adjacent channels are small, the leaked signal components come into question, because the leaked signal components work as interference waves.
The good example is the channel f
2
shown in FIG.
2
. When the sending power of a transmission signal S
2
is small as the channel f
2
, the transmission signal S
2
is buried in the signal components that have been leaked from the adjacent channels f
1
and f
3
; as a result, although the transmission is being performed with the sending power that has been required from the reception side, the signal-to-interference power ratio C/I deteriorates, and it becomes difficult to perform communication satisfactorily.
In this way, even if transmission is performed with the sending power required from the partner of the communication, it is sometimes difficult to maintain the communication satisfactorily because of the influences of the adjacent-channel interference; thus, the conventional transmission power controlling is yet unsatisfactory.
SUMMARY OF THE INVENTION
In view of the foregoing, an object of this invention is to provide a transmitting method, a sending-power controlling method and a transmitting apparatus that uses the methods for avoiding influences of adjacent-channel interference in advance to favorably communicate.
In the transmitting method for forming plural channels in the frequency direction and for transmitting transmission signals on the plural channels with the previously set sending power, with respect to a channel having the largest sending power for the transmission signals among the plural channels, the sending power is determined to the previously set sending power to perform transmission, and with respect to a channel having the next larger sending power for the transmission signals, if the determined channel having the sending power determined exists adjacent to the channel, the previously set sending power is corrected on the basis of the sending power of the determined channel to perform transmission. In addition, in the transmitting method, with respect to a channel having the largest sending power for the transmission signal among the plural channels, the sending power is determined to the previously set sending power to perform transmission, and with respect to channels adjacent to the determined channel having the sending power determined, the previously set sending power is corrected on th
Sakoda Kazuyuki
Suzuki Mitsuhiro
Kuntz Curtis
Maioli Jay H.
Sony Corporation
Taylor Barry W
LandOfFree
Transmitting method and apparatus, and sending power... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transmitting method and apparatus, and sending power..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transmitting method and apparatus, and sending power... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2530719