Telecommunications – Transmitter and receiver at same station – With transmitter-receiver switching or interaction prevention
Reexamination Certificate
2000-03-13
2002-05-07
Hunter, Daniel (Department: 2684)
Telecommunications
Transmitter and receiver at same station
With transmitter-receiver switching or interaction prevention
C455S080000, C455S083000
Reexamination Certificate
active
06385438
ABSTRACT:
The present invention concerns the technical field of antenna arrangements.
Conventionally, an antenna arrangement including an antenna, a receiver and a transmitter, able to couple the antenna alternately to the transmitter (in transmission phase) and to the receiver (in reception phase), is used.
One problem encountered in such an antenna arrangement is achieving an optimum coupling between the transmitter and the antenna.
With reference to
FIG. 1A
of the present description, GB Patent No. 2,323,799 of Motorola Israel discloses an antenna arrangement
10
including an antenna A, a transmitter (the latter including at its output a power amplifier
16
), and means
18
for coupling antenna A and the transmitter.
Coupling means
18
are formed by a transmission line able to transform the output impedance of amplifier
16
, as is described in more detail hereinafter. It will be noted that line
18
operates like a phase lag circuit.
It is to be noted that line
18
allows the transmitter to be isolated from antenna A, in the event that the latter is not in transmission phase (in particular in reception phase). In such case, power amplifier
16
is controlled so as to no longer provide a signal, and its output impedance is then of a highly reactive nature. Line
18
is thus arranged so that the impedance seen from antenna A to the transmitter corresponds to that of an open circuit (high impedance). In other words, the transmitter is insulated from antenna A, and a radiofrequency signal received by antenna A is provided to the receiver.
One drawback of the arrangement of antenna
10
is that it includes transmission lines, which involves a considerable space requirement for this arrangement.
Another drawback of the arrangement of antenna
10
is that it requires making an additional circuit able to control power amplifier
16
, which is counter to the usual industrial concerns as to limiting space requirement, weight, electric power consumption and thus the cost of manufacturing and use.
With reference to
FIG. 1B
of the present description, the document <<Drain supply switching of mobile phone power amps with pulsed operation mode>>, Siemens Application Note No. 009, Discrete and RF semiconductor division, Edition A03, describes a control circuit
23
including control means
25
and a field effect transistor
28
(of P type channel). Transistor
28
is connected between a supply terminal (for receiving supply voltage Vb) and the system's earth, via supply terminals of power amplifier
16
. Transistor
28
is controlled by control means
25
so that, when antenna A is in transmission phase, amplifier
16
can provided a sufficiently powerful radiofrequency signal (RF) from the transmitter to antenna A, with a minimum of electric power loss.
Moreover, the Applicant of the present invention has observed that, when antenna A is in transmission phase, the provision of the radiofrequency signal is not optimum, from the point of view of electric power losses, and that, when antenna A is not in transmission phase, the isolation of the transmitter and antenna A is not optimum, since the output impedance of amplifier
16
can vary.
One object of the present invention is to provide an antenna arrangement including an antenna and a transmitter, this arrangement overcoming the aforementioned drawbacks, to provide optimum coupling between the transmitter and the antenna, i.e. coupling causing a minimum of electric power losses RF.
Another object of the present invention is to provide an antenna arrangement able to provide control of the power amplifier of the transmitter, without resorting to additional components (for example a field effect transistor of P type channel).
Another object of the present invention is to provide an antenna arrangement answering the criteria of minimum complexity, low power consumption, compactness and low cost, which are conventional in telecommunications.
These objects, in addition to others, are achieved by the antenna arrangement according to claim 1.
REFERENCES:
patent: 5193218 (1993-03-01), Shimo
patent: 5590412 (1996-12-01), Sawai et al.
patent: 5678199 (1997-10-01), Birth et al.
patent: 5784687 (1998-07-01), Itoh et al.
patent: 5909641 (1999-06-01), Simmons
patent: 5999523 (1999-12-01), Murtojarvi
patent: 0 714 177 (1996-05-01), None
patent: 0 878 918 (1998-11-01), None
Kucera Jakob
Lott Urs
Zellweger Emil
Asulab S.A.
Sughrue & Mion, PLLC
Tran Tuan
LandOfFree
Antenna arrangement does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Antenna arrangement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Antenna arrangement will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2863345