Method for transmitting signals from a plurality of transmitting units and receiving the signals

N signals are transmitted from each of N transmitting units to a receiving unit every signal transmission cycle (N.gtoreq.2). In this case, N signal transmitting periods of N I-th signals and (N-1) I-th transmission short pausing periods for each of the I-th transmitting units are alternately placed in each of I-th signal grouping periods (1.ltoreq.I.ltoreq.N), and an I-th transmission long pausing period follows each of the I-th signal grouping periods to set one signal transmission cycle composed of one I-th signal grouping period and one I-th transmission long pausing period for each of the I-th transmitting unit. A time length of each first transmission short pausing period is equal to that of the signal transmitting period, a time length of each I-th transmission short pausing period is (2N+2I-5) times as long as that of the signal transmitting period, and a time length of the signal transmission cycle is 4N(N-1) times as long as the signal transmitting period. Therefore, there is no probability that two or more signals for the j-th transmitting unit overlap with two or more signals for the k-th transmitting unit (1.ltoreq.j.ltoreq.N, 1.ltoreq.k.ltoreq.N), and at least one signal not overlapping with any other signal is transmitted from each of the transmitting units to the receiving unit every signal transmission cycle.

BACKGROUND OF THE INVENTION 
1. FIELD OF THE INVENTION 
The present invention relates generally to a signal transmitting and 
receiving method, and more particularly to a method for transmitting 
signals from a plurality of transmitting units at prescribed intervals. 
2. DESCRIPTION OF THE RELATED ART 
A remote control system in which various apparatuses are remote-controlled 
is well-known as an example of a data transmission. In this remote control 
system, data is transmitted from a transmitting unit placed far apart from 
an apparatus to the apparatus through a space for the purpose of 
remote-controlling the apparatus, the transmitted data is received in a 
receiving unit placed in the apparatus and is decoded, and a signal 
corresponding to the decode data is transmitted to the apparatus. 
In general, the remote control system is operated according to a data 
transmitting and receiving method in which pieces of transmission data are 
transmitted from a transmitting unit to a receiving unit at prescribed 
intervals. In a conventional data transmitting and receiving method, only 
a single transmission unit is operated. Also, even though a plurality of 
transmission units are operated the transmission units are not 
simultaneously operated in the conventional data transmitting and 
receiving method. In other words, in cases where a plurality of 
transmitting units placed in a limited area are simultaneously operated or 
in cases where a plurality of transmission signals overlapped with each 
other are transmitted from a plurality of transmitting units, it is 
impossible to decode the transmission signals overlapped with each other 
in a receiving unit of an apparatus. Therefore, there is a drawback that 
the apparatus cannot be remote-controlled. 
To solve the above drawback, a first conventional data transmitting and 
receiving method in which a data transmission interval adopted in one 
transmitting unit differs from that in another transmitting unit is 
well-known. Also, a second conventional data transmitting and receiving 
method in which a plurality of transmission frequencies are used according 
to a frequency multiplexing method is well-known. Also, a conventional 
polling method in which a two-way communication is performed and a 
transmission timing at each of a plurality of transmitting units is 
regulated is well-known. 
2.1. PREVIOUSLY PROPOSED ART 
An example of the first conventional data transmitting and receiving method 
is described with reference to FIG. 1. 
FIG. 1 shows a timing chart of three series of signals transmitted from 
three transmitting units according to the first conventional data 
transmitting and receiving method. 
As shown in FIG. 1, a plurality of first signals S1 respectively having a 
signal width are transmitted from a first transmitting unit at first 
specific intervals, a plurality of second signals S2 respectively having 
the same signal width are transmitted from a second transmitting unit at 
second specific intervals, and a plurality of third signals S3 
respectively having the same signal width are transmitted from a third 
transmitting unit at third specific intervals. The signal width for the 
first, second and third signals is called a signal transmitting period T, 
a period in which any first signal S1 is not transmitted is called a first 
signal transmission pausing period X1, a period in which any second signal 
S2 is not transmitted is called a second signal transmission pausing 
period X2, and a period in which any third signal S3 is not transmitted is 
called a third signal transmission pausing period X3. 
In cases where the signal transmission pausing periods X1, X2 and X3 differ 
from each other, a part of the first signals S1 are not simultaneously 
transmitted with any second or third signal. That is, the part of the 
first signals S1 are transmitted to a receiving unit without overlapping 
with any second or third signal. Also, a part of the second signals S2 are 
transmitted to the receiving unit without overlapping with any first or 
second signal, and a part of the third signals S3 are transmitted to the 
receiving unit without overlapping with any first or second signal. 
Accordingly, when the first, second and third signals are continued to be 
transmitted to the receiving unit for a prescribed period or more, even 
though the first, second and third transmitting units are simultaneously 
operated, the first, second and third signals can be reliably transmitted 
to the receiving unit. 
2.2. PROBLEMS TO BE SOLVED BY THE INVENTION 
However, because the transmission of the first, second and third signals to 
the receiving unit is performed when each of the signals is not overlapped 
with any other signal by chance, the first, second and third signals 
cannot be reliably transmitted to the receiving unit unless the first, 
second and third signals are continued to be transmitted to the receiving 
unit for a prescribed period or more. 
Also, in cases where the number of transmitting units is increased, a 
probability that the signals are simultaneously overlapped with each other 
is increased, and there is a drawback that a probability that the signals 
are reliably transmitted to the receiving unit is decreased. 
Also, in the second conventional data transmitting and receiving method, 
because a plurality of frequencies are used, there is a drawback that 
complicated circuits such as a modulation circuit, a synchronizing circuit 
and the like and expensive parts are required. 
Also, in the third conventional data transmitting and receiving method, 
because two-way communication is performed between a pair of apparatuses, 
a transmitting unit and a receiving unit are required for each of the 
apparatuses. Therefore, there is a drawback that each of the apparatuses 
is manufactured in a large size and is expensive. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide, with due consideration to 
the drawbacks of such a conventional data transmitting and receiving 
method, a method for transmitting signals from a plurality of transmitting 
units at prescribed intervals in which the signals are reliably 
transmitted to a receiving unit even though the number of transmitting 
units is increased and the receiving and transmitting units are 
simplified. 
The object is achieved by the provision of a data transmitting and 
receiving method, comprising the steps of: 
preparing M signals (M is an integral number higher than 2) respectively 
having a signal transmitting period as a signal width in each of N 
transmitting units (N is an integral number higher than 2, and 
N.ltoreq.M), a time length of the signal transmitting period being in 
common to the N transmitting units; 
alternately arranging the signal transmitting periods of the M signals and 
(M-1) transmission short pausing periods in a signal grouping period for 
each of the N transmitting units to place the M signals at equal 
intervals; 
adjusting N time lengths of N groups of the (M-1) transmission short 
pausing periods respectively corresponding one of the N transmitting units 
on condition that two or more signals of one transmitting unit do not 
overlap with two or more signals of each of the other transmitting units; 
setting a signal transmitting cycle having a common time length to the N 
transmitting units, to place each of the signal grouping periods having 
different time lengths in the signal transmitting cycle for each of the N 
transmitting units; and 
transmitting the M signals respectively spaced by the transmission short 
pausing period, of which the time length is adjusted, from each of the N 
transmitting units to a receiving unit every signal transmitting cycle. 
In the above steps, M signals are transmitted from each of N transmitting 
units to a receiving unit every signal transmitting cycle. In this case, 
each of the signal transmitted from the transmitting units has the same 
signal transmitting period as a signal width, the M signals are equally 
spaced by a transmission short pausing period, the transmission short 
pausing period for one transmitting unit differs from that for another 
transmitting unit on condition that two or more signals transmitted from 
one transmitting unit do not overlap with two or more signals transmitted 
from each of the other transmitting units. 
Accordingly, at least one signal transmitted from each of the transmitting 
units does not overlap with any signal transmitted from one of the other 
transmitting units and is received by the receiving unit as an effective 
signal. Therefore, data indicated by a series of effective signals in a 
series of signal transmission cycles can be reliably transmitted from each 
transmitting unit to the receiving unit. 
Also, because the M signals transmitted from each of the transmitting units 
are equally spaced, A configuration of each transmitting unit can be 
simplified. 
It is preferred that the step of preparing M signals includes the step of: 
classifying the N transmitting units into a first transmitting unit and one 
or more I-th transmitting units (I is an integral number, and 
2.ltoreq.I.ltoreq.N), and 
the step of adjusting N time lengths of N groups of the (M-1) transmission 
short pausing periods, comprises the steps of: 
adjusting the (M-1) transmission short pausing periods for the first 
transmitting unit to a common time length equal to that of the signal 
transmitting period; and 
adjusting the (M-1) transmission short pausing periods for each of the I-th 
transmitting units to another common time length which is (2*N+2*I-5) or 
more times as long as that of the signal transmitting period. 
In the above steps, because the signal grouping period for the first 
transmitting unit is equal to or shorter than any of the I-th transmission 
short pausing periods for the I-th transmitting units, there is no 
probability that two or more signals for the first transmitting unit 
overlap with two or more signals for one of the other transmitting units. 
Also, because a summed time length of one I-th transmission short pausing 
period for the I-th transmitting unit and two signal transmitting periods 
is equal to or shorter than one (I+1)-th transmission short pausing period 
for the (I+1)-th transmitting unit and because a summed time length of two 
second transmission short pausing periods for the second transmitting unit 
and one signal transmitting period is equal to or longer than another 
summed time length of one N-th transmission short pausing period for the 
N-th transmitting unit and two signal transmitting periods, there is no 
probability that two or more signals for the j-th transmitting unit 
overlap with two or more signals for the k-th transmitting unit 
(2.ltoreq.j.ltoreq.N, 2.ltoreq.k.ltoreq.N). 
Also, it is preferred that the step of preparing M signals includes the 
step of: 
calling the N transmitting units a plurality of I-th transmitting units (I 
is an integral number, and 1.ltoreq.I.ltoreq.N), and 
the step of adjusting N time lengths of N groups of the (M-1) transmission 
short pausing periods, comprises the step of: 
adjusting the (M-1) transmission short pausing periods for each of the I-th 
transmitting units to a common time length which is (2*N+2*I-3) or more 
times as long as that of the signal transmitting period. 
In the above steps, because a summed time length of one I-th transmission 
short pausing period for the I-th transmitting unit and two signal 
transmitting periods is equal to or shorter than one (I+1)-th transmission 
short pausing period for the (I+1)-th transmitting unit and because a 
summed time length of two second transmission short pausing periods for 
the second transmitting unit and one signal transmitting period is equal 
to or longer than another summed time length of one N-th transmission 
short pausing period for the N-th transmitting unit and two signal 
transmitting periods, there is no probability that two or more signals for 
the j-th transmitting unit overlap with two or more signals for the k-th 
transmitting unit (2.ltoreq.j.ltoreq.N, 2.ltoreq.k.ltoreq.N). 
Also, it is preferred that the step of preparing M signals includes the 
step of: 
calling the N transmitting units a plurality of I-th transmitting units (I 
is an integral number, and 1.ltoreq.I.ltoreq.N), and 
the step of adjusting N time lengths of N groups of the (M-1) transmission 
short pausing periods, comprises the step of: 
adjusting the (M-1) transmission short pausing periods for each of the I-th 
transmitting units to a common time length on condition that each of the 
transmission short pausing periods for the (I+1)-th transmitting unit is 
equal to or longer than the signal grouping period for the I-th 
transmitting unit. 
In the above steps, because the (I+1)-th transmitting unit is equal to or 
longer than the signal grouping period for the I-th transmitting unit, 
there is no probability that two or more signals for the j-th transmitting 
unit overlap with two or more signals for the k-th transmitting unit 
(2.ltoreq.j.ltoreq.N, 2.ltoreq.k.ltoreq.N).

DETAILED DESCRIPTION OF THE EMBODIMENTS 
Preferred embodiments of a method for transmitting signals from a plurality 
of transmitting units at prescribed intervals according to the present 
invention are described with reference to drawings. 
FIG. 2 shows a timing chart of a series of signals transmitted from a 
transmitting unit according to the present invention. 
As shown in FIG. 2, three signals S are transmitted every signal 
transmission cycle C, each of signal transmission cycles C is partitioned 
into a signal grouping period U and a transmission long pausing period Xd 
following the signal grouping period U, three signal transmission periods 
T and two transmission short pausing periods Xs are alternately placed in 
each of signal grouping periods U. The two transmission short pausing 
periods Xs and the transmission long pausing period Xd are generically 
called a signal transmission pausing period. 
First Embodiment 
FIG. 3A shows a timing chart of three series of signals transmitted from 
three transmitting units according to a first embodiment of the present 
invention. 
As shown in FIG. 3A, in cases where the number of transmitting units is 
indicated by a value N, N signals are transmitted from each of 
transmitting units every signal transmission cycle C. For example, in case 
of N=3, three first signals S1 respectively having a signal transmission 
period T as a signal width are transmitted from a first transmitting unit 
TU1, three signal transmission periods T and two first transmission short 
pausing periods Xs1 are alternately placed in each of first signal 
grouping periods U1 to equally space the first signals S1 by the first 
transmission short pausing period Xs1, and a first transmission long 
pausing period Xd1 is placed after the first signal grouping period U1 in 
each of the signal transmission cycle C. The first transmission short 
pausing period Xs1 is equal to the signal transmission period T (Xs1=T). 
Therefore, the first signal grouping period U1 is five times as long as 
the signal transmission period T (U1=5*T). 
Also, three second signals S2 respectively having the same signal 
transmission period T as a signal width are transmitted from a second 
transmitting unit TU2, three signal transmission periods T and two second 
transmission short pausing periods Xs2 are alternately placed in each of 
second signal grouping periods U2 to equally space the second signals S2 
by the second transmission short pausing period Xs2, and a second 
transmission long pausing period Xd2 is placed after the second signal 
grouping period U2 in each of the signal transmission cycle C. 
Also, three third signals S3 respectively having the same signal 
transmission period T as a signal width are transmitted from a third 
transmitting unit TU3, three signal transmission periods T and two third 
transmission short pausing periods Xs3 are alternately placed in each of 
third signal grouping periods U3 to equally space the third signals S3 by 
the third transmission short pausing period Xs3, and a third transmission 
long pausing period Xd3 is placed after the third signal grouping period 
U3 in each of the signal transmission cycle C. 
In cases where the number of the transmitting unit TUi 
(2.ltoreq.i.ltoreq.n) is indicated by a value I (I is an integral number 
higher than 1), the transmission short pausing period Xsi except the first 
transmission short pausing period Xs1 is (2*N+2*I-5) times as long as the 
signal transmission period T. That is, because a relationship of N=3 and 
I=2 is satisfied for the second signals S2, the second transmission short 
pausing period Xs2 is five times as long as the signal transmission period 
T (Xs2=5T). Because the three signal transmission periods T and the two 
second transmission short pausing periods Xs2 are alternately placed in 
the second signal grouping period U2, a relationship U2=13*T is obtained. 
Also, because N=3 and I=3 is satisfied for the third signals S3, the third 
transmission short pausing period Xs3=(2*N+2*I-5)T is seven times as long 
as the signal transmission period T (Xs3=7T). Because the three signal 
transmission periods T and the two third transmission short pausing 
periods Xs3 are alternately placed in the third signal grouping period U3, 
a relationship U3=17*T is obtained. 
The third transmission long pausing period Xd3 is set to be equal to the 
third transmission short pausing period Xs3 because the period Xd3 is the 
final transmission long pausing period (Xd3=Xs3=7T), so that the signal 
transmission cycle C is set to 24T because the third signal grouping 
period U3 is 17T. In this case, the first transmission long pausing period 
Xd1 is set to 19T because the first signal grouping period U1 is 5T, and 
the second transmission long pausing period Xd2 is set to 11T because the 
second signal grouping period U2 is 13T. 
In general, as shown in FIG. 3B, in cases where N types of signals are 
simultaneously transmitted from N transmitting units, N signals are 
transmitted from each of N transmitting units every signal transmission 
cycle. In the first transmitting unit TU1, because N signal transmission 
periods T for N first signals S1 and (N-1) first transmission short 
pausing periods Xs1=T are alternately placed in the first signal grouping 
period U1, a relationship U1=(2N-1)T is determined. In the i-th 
transmitting unit UNi (i=2, 3, - - - , n), because N signal transmission 
periods T for N i-th signals Si and (N-1) i-th transmission short pausing 
periods Xsi=(2N+2I-5)T are alternately placed in the i-th signal grouping 
period Ui, a relationship Ui={N+(N-1)(2N+2I-5)}T is determined. Also, 
because the final transmission short pausing period Xsn is (4N-5)T, the 
final transmission long pausing period Xdn is set to (4N-5)T. Because the 
final signal grouping period Un is (4N.sup.2 -8N+5)T, the signal 
transmission cycle C is set to 4N(N-1)T. In this case, because of the i-th 
signal grouping period Ui={N+(N-1)(2N+2I-5)}T, the i-th transmission long 
pausing period Xdi={4N(N-1)-N-(N1)*(2N+2I-5)}T is placed after the i-th 
signal grouping period Ui for each signal transmission cycle C. Also, 
because of the first signal grouping period U1=(2N-1)T, the first 
transmission long pausing period Xd1=(4N.sup.2 -6N+1)T is placed after the 
first signal grouping period U1 for each signal transmission cycle C. 
In the above signal transmitting and receiving method, as shown in FIG. 4, 
the (i+1)-th transmission short pausing period Xs(i+1) is longer than the 
i-th transmission short pausing period Xsi by 2T. Therefore, even though 
the transmission timing of the i-th signals Si shifts from that of the 
(i+1)-th signals S(i+1) by any time period, there is no probability that 
two or more i-th signals Si simultaneously overlap with two or more 
(i+1)-th signals S(i+1). Also, because the i-th transmission short pausing 
period Xsi is longer than the first transmission short pausing period Xs1 
by I*T, there is no probability that two or more first signals S1 
simultaneously overlap with another type of signals Si. 
Also, as shown in FIG. 5, in cases where a first period Xsn+2T obtained by 
adding the final transmission short pausing period Xsn and two signal 
transmitting periods T is longer than a second period 2Xs2+T obtained by 
adding two second transmission short pausing periods Xs2 and one signal 
transmitting period T, there is a probability that two j-th signals Sj 
(j.gtoreq.2) transmitted from the j-th transmitting unit TUj 
simultaneously overlap with two k-th signals Sk (k.gtoreq.2) transmitted 
from the transmitting unit Tuk in one signal transmitting cycle C. 
However, because the first period Xsn+2T is equal to (4N-3)*T and the 
second period 2Xs2+T is equal to (4N-1)*T, there is no probability that 
two or more j-th signals Sj simultaneously overlap with two or more 
signals Sk. 
Accordingly, there is no probability that all N signals transmitted from 
one transmitting unit simultaneously overlaps with other signals 
transmitted from the other transmitting units, and one or more signals 
transmitted from one transmitting unit is reliably received by a receiving 
unit without overlapping with other signals transmitted from the other 
transmitting units. That is, because one signal not overlapping with any 
other signal is transmitted to the receiving unit for each signal 
transmission cycle C, it is judged in the receiving unit whether or not 
each of the N signals transmitted from one transmitting unit overlaps with 
another signal transmitted from one of the other transmitting units, one 
or more signals overlapped with other signals are abandoned, and at least 
one signal not overlapping with any other signal is received by the 
receiving unit as an effective signal for each signal transmission cycle 
C. Therefore, data indicated by a series of effective signals in a series 
of signal transmission cycles c can be reliably transmitted from each 
transmitting unit to the receiving unit. 
Also, because a plurality of signals Si is transmitted from each 
transmitting unit TUi at a regular frequency Xsi+T and the transmission of 
the signals Si is stopped for a regular transmission long pausing period 
Xdi, the transmitting unit and the receiving unit can be simplified. 
Also, because the method for transmitting signals from a plurality of 
transmitting units and receiving the signals in a receiving unit can be 
applied for a one-way communication, the transmitting unit and the 
receiving unit can be moreover simplified, and a small sized signal 
transmitting and receiving system can be manufactured at a low cost. 
In this embodiment, the first transmission short pausing period Xs1 is set 
to the signal transmission period T to shorten the signal transmission 
cycle C to a minimum period. However, it is applicable that the first 
transmission short pausing period Xs1 is longer than the signal 
transmission period T. 
The reason that the first transmission short pausing period Xs1 is set to 
the signal transmission period T is described with reference to FIG. 6. 
As shown in FIG. 6, in cases where the first transmission short pausing 
period Xs1 is shorter than the signal transmission period T, there is a 
probability that two first signals S1 simultaneously overlap with one 
signal Si transmitted from another transmitting unit TUi.In this case, 
even though N first signals S1 are transmitted from the first transmitting 
unit every signal transmission cycle C, there is a case that all N first 
signals S1 simultaneously overlap with other signals transmitted from the 
other transmitting units. Therefore, it is required that the first 
transmission short pausing period Xs1 is equal to or more than the signal 
transmission period T (Xs1.gtoreq.T), and the signal transmission cycle C 
is minimized in cases where the first transmission short pausing period 
Xs1 is equal to the signal transmission period T. 
Next, the reason that the transmission short pausing period Xsi except the 
first transmission short pausing period Xs1 is set to a value (2*N 30 
2*I-5)*T is described with reference to FIG. 7. 
Because U1=N*T+(N-1)*Xs1 and Xs1.gtoreq.T are satisfied, a relationship 
EQU U1.gtoreq.(2*N-1)*T 
is obtained. As shown in FIG. 7, in cases where the second transmission 
short pausing period Xs2 is equal to or longer than the first signal 
grouping period U1 (Xs2.gtoreq.U1), there is no probability that two or 
more first signals S1 simultaneously overlap with two or more second 
signals S2. 
Therefore, a relationship 
EQU Xs2.gtoreq.(2*N-1)*T 
is obtained. In cases where the (i+1)-th transmission short pausing period 
Xs(i+1) is longer than the i-th transmission short pausing period Xsi by 
2*T or more, because there is no probability that two or more i-th signals 
Si simultaneously overlap with two or more (i+1) signals S(i+1), a 
relationship 
EQU Xsi.gtoreq.(2*N-1)*T+2(I-2)*T 
is obtained. Therefore, 
EQU Xsi.gtoreq.(2*N+2*I-5)*T (I.gtoreq.2) (1) 
is obtained. In cases of Xsi=(2*N+2*I-5)*T, the signal transmission cycle C 
is minimized. 
Next, the reason that the signal transmission cycle C is set to 4N(N-1)*T 
is described in detail. 
The signal transmission cycle C is obtained by adding the i-th signal 
grouping period Ui and the transmission long pausing period Xdi, and 
U(i+1)&gt;Ui is satisfied. Also, the transmission long pausing period Xdi is 
longer than the transmission short pausing period Xsi, and Xs(i+1)&gt;Xsi is 
satisfied. Therefore, because Un.gtoreq.Ui and Xsn.gtoreq.Xsi are 
satisfied (Un denotes the signal grouping period for the final 
transmitting unit TUn, and Xsn denotes the transmission short pausing 
period for the final transmitting unit TUn), 
EQU C=Un+Xdn (2) 
Xdn.gtoreq.Xsn 
is obtained. Because a relationship 
EQU Un.gtoreq.N*T+(N-1)*Xsn (3) 
is obtained, a relationship 
EQU C.gtoreq.N*T+(N-1)*Xsn+Xsn 
is obtained. That is, 
EQU C.gtoreq.N*(T+Xsn) (4) 
is satisfied. 
Because of Xsi.gtoreq.(2*N+2*I-5)*T in the equation (1), a relationship 
EQU Xsn.gtoreq.(2*N+2*N 5)*T.gtoreq.(4*N-5)*T (5) 
is obtained. Therefore, a relationship is obtained from the equations (4) 
and (5). 
EQU C.gtoreq.N*{T+(4*N-5)*T}.gtoreq.4N*(N-1)*T 
In case of C=4N*(N-1)*T, the signal transmission cycle C is minimized. 
Therefore, in cases where the signal transmitting period T is equal to 10 
msec, the signal transmission cycle C is 80 msec when two transmitting 
units are used, the signal transmission cycle C is 240 msec when three 
transmitting units are used, and the signal transmission cycle C is 480 
msec when four transmitting units are used. 
In this embodiment, three transmitted units are used. However, the number 
of transmitted units is not limited. 
Also, the periods Ui, Xsi, Xdi and the cycle C are determined to minimize 
the cycle C. However, it is applicable that the periods Ui, Xsi, Xdi and 
the cycle C be lengthened. 
Also, N signals are transmitted from each transmitting unit in cases where 
the number of transmitting units is N. However, it is applicable that a 
plurality of signals more than N be transmitted from each transmitting 
unit in cases where the number of transmitting units is N. 
Also, N types of signals transmitted from N transmitting units are received 
in a receiving unit. However, it is applicable that N receiving units be 
prepared and each type of signals transmitted from one transmitting unit 
be received in a corresponding receiving unit. 
Also, each type of signals are transmitted through a wire route or a 
radio-frequency route. Also, this embodiment is available for a one-way 
communication and a two-way communication. Also, this embodiment is 
available for an infrared ray communication and a sound wave 
communication. 
Second Embodiment 
FIG. 8A shows a timing chart of three series of signals transmitted from 
three transmitting units according to a second embodiment of the present 
invention. 
As shown in FIG. 8A, in cases where the number of transmitting units is 
indicated by a value N, N signals are transmitted from each of 
transmitting units every signal transmission cycle C. For example, in case 
of N=3, three first signals S1 respectively having a signal transmission 
period T as a signal width are transmitted from a first transmitting unit 
TU1, three signal transmission periods T and two first transmission short 
pausing periods Xs1 are alternately placed in each of first signal 
grouping periods U1 to equally space the first signals S1 by the first 
transmission short pausing period Xs1, and a first transmission long 
pausing period Xd1 is placed after the first signal grouping period U1 in 
each of the signal transmission cycle C. 
Also, three second signals S2 respectively having the same signal 
transmission period T as a signal width are transmitted from a second 
transmitting unit TU2, three signal transmission periods T and two second 
transmission short pausing periods Xs2 are alternately placed in each of 
second signal grouping periods U2 to equally space the second signals S2 
by the second transmission short pausing period Xs2, and a second 
transmission long pausing period Xd2 is placed after the second signal 
grouping period U2 in each of the signal transmission cycle C. 
Also, three third signals S3 respectively having the same signal 
transmission period T as a signal width are transmitted from a third 
transmitting unit TU3, three signal transmission periods T and two third 
transmission short pausing periods Xs3 are alternately placed in each of 
third signal grouping periods U3 to equally space the third signals S3 by 
the third transmission short pausing period Xs3, and a third transmission 
long pausing period Xd3 is placed after the third signal grouping period 
U3 in each of the signal transmission cycle C. 
In cases where the number of the transmitting unit TUi 
(1.ltoreq.i.ltoreq.n) is indicated by a value I (I is an integral number 
higher than 1), the transmission short pausing period Xsi is (2*N+2*I-3) 
times as long as the signal transmission period T. That is, because a 
relationship of N=3 and I=1 is satisfied for the first signals S1, the 
first transmission short pausing period Xs1 is five times as long as the 
signal transmission period T (Xs1=5T). Because the three signal 
transmission periods T and the two first transmission short pausing 
periods Xs1 are alternately placed in the first signal grouping period U1, 
a relationship U1=13*T is obtained. Also, because a relationship of N=3 
and I=2 is satisfied for the second signals S2, the second transmission 
short pausing period Xs2=(2*N+2*I-5)T is seven times as long as the signal 
transmission period T (Xs2=7T). Because the three signal transmission 
periods T and the two second transmission short pausing periods Xs2 are 
alternately placed in the second signal grouping period U2, a relationship 
U2=17*T is obtained. 
Also, because N=3 and I=3 is satisfied for the third signals S3, the third 
transmission short pausing period Xs3=(2*N+2*I-5)T is nine times as long 
as the signal transmission period T (Xs3=9T). Because the three signal 
transmission periods T and the two third transmission short pausing 
periods Xs3 are alternately placed in the third signal grouping period U3, 
a relationship U3=21*T is obtained. 
The third transmission long pausing period Xd3 is set to be equal to the 
third transmission short pausing period Xs3 (Xd3=Xs3=9T) because the 
period Xd3 is the final transmission long pausing period, so that the 
signal transmission cycle C is set to 30T because the third signal 
grouping period U3 is 21T. In this case, the first transmission long 
pausing period Xd1 is set to 17T because the first signal grouping period 
U1 is 13T, and the second transmission long pausing period Xd2 is set to 
13T because the second signal grouping period U2 is 17T. 
In general, as shown in FIG. 8B, in cases where the number of transmitting 
units is N, N signals are transmitted from each of N transmitting units 
every signal transmission cycle C. In the i-th transmitting unit UNi (i=1, 
2, - - - , n), because N signal transmission periods T for N i-th signals 
Si and (N-1) i-th transmission short pausing periods Xsi=(2N+2I-3)T are 
alternately placed in the i-th signal grouping period Ui, a relationship 
Ui={N+(N-1)(2N+2I-3)}T is determined. Also, because the final transmission 
short pausing period Xsn is (4N-3)T, the final transmission long pausing 
period Xdn is set to (4N-3)T. Because the final signal grouping period Un 
is (4N.sup.2 -6N+3)T, the signal transmission cycle C is set to 2N(2N-1)T. 
In this case, because of the i-th signal grouping period 
Ui={N+(N-1)(2N+2I-3)}T, the i-th transmission long pausing period 
Xdi={2N(2N-1)-N-(N-1)(2N+2I-3)}T is placed after the i-th signal grouping 
period Ui for each signal transmission cycle C. 
In the above signal transmitting and receiving method, N types of signals 
are simultaneously transmitted from N transmitting units to a receiving 
unit, and N signals are transmitted from each of N transmitting units 
every signal transmission cycle C=2N(2N-1)T. In the i-th transmitting unit 
UNi (i=1,2, - - - , n), N signal transmission periods T for N i-th signals 
Si equally spaced by the (N-1) i-th transmission short pausing periods 
Xsi=(2N+2I-5)T are arranged in the i-th signal grouping period 
Ui={N+(N-1)(2N+2I-3)}T of each signal transmission cycle C, and the i-th 
transmission long pausing period Xdi={2(N+1)(N-I)+4I-3}T follows the i-th 
signal grouping period Ui for each signal transmission cycle C. 
The reason that the transmission short pausing period Xsi is set to a value 
(2N+2I-3)T is described with reference to FIG. 9. 
As shown in FIG. 9, in cases where a first period Xsn+2T obtained by adding 
the final transmission short pausing period Xsn and two signal 
transmitting periods T is longer than a second period 2Xs1+T obtained by 
adding two first transmission short pausing periods Xs1 and one signal 
transmitting period T, there is a probability that two j-th signals Sj 
(j.gtoreq.2) transmitted from the j-th transmitting unit TUj 
simultaneously overlap with two k-th signals Sk (k.gtoreq.2) transmitted 
from the transmitting unit TUk in one signal transmitting cycle C. To 
prevent that two j-th signals Sj simultaneously overlap with two k-th 
signals Sk, a relationship 
EQU 2Xs1+T.gtoreq.Xsn+2T 
is required. That is, it is required to satisfy a relationship between the 
first transmission short pausing period Xs1 and the final transmission 
short pausing period Xsn as follows. 
EQU 2Xs1-T.gtoreq.Xsn (6) 
Also, in cases where the (i+1)-th transmission short pausing period Xs(i+1) 
is longer than the i-th transmission short pausing period Xsi by 2T or 
more (Xs(i+1).gtoreq.Xsi+2T), because there is no probability that two or 
more i-th signal Si simultaneously overlap with two or more (i+1)-th 
signal S(i+1), it is required to satisfy a relationship between the first 
transmission short pausing period Xs1 and the i-th transmission short 
pausing period Xsi as follows. 
EQU Xsi.gtoreq.Xs1+2(I-1)*T (7) 
Therefore, another relationship between the transmission short pausing 
periods Xs1 and Xsn is obtained according to the equation (7). 
EQU Xsn.gtoreq.Xs1+2(N-1)*T (8) 
Therefore, a relationship 
EQU 2Xs1-T.gtoreq.Xs1+2(N-1)*T 
is obtained according to the equations (6) and (8). That is, an equation 
(9) is obtained. 
EQU Xs1.gtoreq.(2N-1)*T (9) 
Therefore, a condition for the i-th transmission short pausing period Xsi 
is obtained according to the equations (7) and (9). 
EQU Xsi.gtoreq.(2N-1)*T+2(I-1)*T 
That is, an equation (10) is obtained. 
EQU Xsi.gtoreq.(2N+2I-3)*T (10) 
That is, in cases where the i-th transmission short pausing periods Xsi are 
determined on condition that the equation (10) is satisfied, because the 
first period 2Xs1+T is equal to or shorter than the second period Xsn+2T 
and the (i+1)-th transmission short pausing period Xs(i+1) is longer than 
the i-th transmission short pausing period Xsi by 2T or more, there is no 
probability that two or more j-th signals Sj transmitted from one 
transmitting unit TUj simultaneously overlap with two or more k-th signals 
Sk transmitted from another transmitting unit TUk in one signal 
transmitting cycle C even though the transmission timing of the signals Sj 
shifts from that of the signals Sk by any time period. 
Accordingly, there is no probability that all N signals transmitted from 
one transmitting unit simultaneously overlaps with other signals 
transmitted from the other transmitting units, and one or more signals 
transmitted from one transmitting unit is reliably received by a receiving 
unit without overlapping with other signals transmitted from the other 
transmitting units. That is, because one signal not overlapping with any 
other signal is transmitted to the receiving unit for each signal 
transmission cycle C, data indicated by a series of signals in a series of 
signal transmission cycles C can be reliably transmitted from each 
transmitting unit to the receiving unit. 
Also, because a plurality of signals Si is transmitted from each 
transmitting unit TUi at a regular frequency Xsi+T and the transmission of 
the signals Si is stopped for a regular transmission long pausing period 
Xdi, the transmitting unit and the receiving unit can be simplified. 
Also, because the method for transmitting signals from a plurality of 
transmitting units and receiving the signals in a receiving unit can be 
applied for a one-way communication, the transmitting unit and the 
receiving unit can be moreover simplified, and a small sized signal 
transmitting and receiving system can be manufactured at a low cost. 
Next, the reason that the signal transmission cycle C is set to 2N(2N-1)*T 
is described in detail. 
The signal transmission cycle C is obtained by adding the i-th signal 
grouping period Ui and the transmission long pausing period Xdi, and 
U(i+1)&gt;Ui is satisfied. Also, the transmission long pausing period Xdi is 
longer than the transmission short pausing period Xsi, and Xs(i+1)&gt;Xsi is 
satisfied. Therefore, because Un.gtoreq.Ui and Xsn.gtoreq.Xsi are 
satisfied (Un denotes the signal grouping period for the final 
transmitting unit TUn, and Xsn denotes the transmission short pausing 
period for the final transmitting unit TUn), 
EQU C=Un+Xdn (11) 
Xdn.gtoreq.Xsn 
is obtained. Because a relationship 
EQU Un.gtoreq.N*T+(N-1)*Xsn 
is obtained, a relationship 
EQU C.gtoreq.N*T+(N-1)*Xsn+Xsn 
is obtained. That is, 
EQU C.gtoreq.N*(T+Xsn) (12) 
is satisfied. 
Because of Xsi.gtoreq.(2*N+2*I-3)*T in the equation (10), a relationship 
EQU Xsn.gtoreq.(2*N+2*N-3)*T.gtoreq.(4*N-3)*T (13) 
is obtained. Therefore, a relationship is obtained from the equations (12) 
and (13). 
EQU C.gtoreq.N*{T+(4*N-3)*T}2N*(2N-1)*T 
In case of C=2N*(2N-1)*T, the signal transmission cycle C is minimized. 
Therefore, in cases where the signal transmitting period T is equal to 10 
msec, the signal transmission cycle C is 120 msec when two transmitting 
units are used, the signal transmission cycle C is 300 msec when three 
transmitting units are used, and the signal transmission cycle C is 560 
msec when four transmitting units are used. 
In this embodiment, the transmission short pausing periods Xsi are set to 
satisfy the relationship Xsi=(2N+2I-3)*T. However, it is applicable that 
the transmission short pausing periods Xsi be set to satisfy the 
relationship Xsi&gt;(2N+2I-3)*T. 
Also, three transmitted units are used. However, the number of transmitted 
units is not limited. 
Also, the periods Ui, Xsi, Xdi and the cycle C are determined to minimize 
the cycle C. However, it is applicable that the periods Ui, Xsi, Xdi and 
the cycle C be lengthened. 
Also, N signals are transmitted from each transmitting unit in cases where 
the number of transmitting units is N. However, it is applicable that a 
plurality of signals more than N be transmitted from each transmitting 
unit in cases where the number of transmitting units is N. 
Also, N types of signals transmitted from N transmitting units are received 
in a receiving unit. However, it is applicable that N receiving units be 
prepared and each type of signals transmitted from one transmitting unit 
be received in a corresponding receiving unit. 
Third Embodiment 
FIG. 10 shows a timing chart of three series of signals transmitted from 
three transmitting units according to a third embodiment of the present 
invention. 
As shown in FIG. 10, in cases where the number of transmitting units is 
indicated by a value N, N signals are transmitted from each of 
transmitting units every signal transmission cycle C. For example, in case 
of N=3, three first signals S1 respectively having a signal transmission 
period T as a signal width are transmitted from a first transmitting unit 
TU1, three signal transmission periods T and two first transmission short 
pausing periods Xs1 are alternately placed in each of first signal 
grouping periods U1 to equally space the first signals S1 by the first 
transmission short pausing period Xs1, and a first transmission long 
pausing period Xd1 is placed after the first signal grouping period U1 in 
each of the signal transmission cycle C. The first transmission short 
pausing period Xs1 is equal to the signal transmission period T (Xs1=T). 
Therefore, the first signal grouping period U1 is five times as long as 
the signal transmission period T (U1=5*T). 
Also, three second signals S2 respectively having the same signal 
transmission period T as a signal width are transmitted from a second 
transmitting unit TU2, three signal transmission periods T and two second 
transmission short pausing periods Xs2 are alternately placed in each of 
second signal grouping periods U2 to equally space the second signals S2 
by the second transmission short pausing period Xs2, and a second 
transmission long pausing period Xd2 is placed after the second signal 
grouping period U2 in each of the signal transmission cycle C. 
Also, three third signals S3 respectively having the same signal 
transmission period T as a signal width are transmitted from a third 
transmitting unit TU3, three signal transmission periods T and two third 
transmission short pausing periods Xs3 are alternately placed in each of 
third signal grouping periods U3 to equally space the third signals S3 by 
the third transmission short pausing period Xs3, and a third transmission 
long pausing period Xd3 is placed after the third signal grouping period 
U3 in each of the signal transmission cycle C. 
The second transmission short pausing period Xs2 is equal to the first 
signal grouping period U1 (Xs2=U1=5T). Because the three signal 
transmission periods T and the two second transmission short pausing 
periods Xs2 are alternately placed in the second signal grouping period 
U2, the second signal grouping period U2 is equal to 13T. Also, the third 
transmission short pausing period Xs3 is equal to the second signal 
grouping period U1 (Xs3=U2=13T). Because the three signal transmission 
periods T and the two third transmission short pausing periods Xs3 are 
alternately placed in the third signal grouping period U3, the third 
signal grouping period U3 is equal to 29T. 
The third transmission long pausing period Xd3 is equal to the third 
transmission short pausing period Xs3 (Xd3=Xs3=13T). Therefore, the signal 
transmission cycle C is set to 42T obtained by adding the third signal 
grouping period U3 and the third transmission long pausing period Xd3, the 
second transmission long pausing period Xd2 is equal to 29T obtained by 
subtracting the second signal grouping period U2 from the signal 
transmission cycle C, and the first transmission long pausing period Xd1 
is equal to 37T obtained by subtracting the first signal grouping period 
U1 from the signal transmission cycle C. 
In general, in cases where N types of signals are simultaneously 
transmitted from N transmitting units (N.noteq.2), N signals are 
transmitted from each of N transmitting units every signal transmission 
cycle C. In the i-th transmitting unit UNi (i=1,2, - - - , n), the i-th 
transmission short pausing period Xsi is set to a time length 
{2/(N-2)*(N-1)i-N/(N-2)}*T because of a relationship Xsi*(N-1)+N=Xs(i+1). 
In this case, because N signal transmission periods T for N i-th signals 
Si and (N-1) i-th transmission short pausing periods Xsi are alternately 
placed in the i-th signal grouping period Ui, a relationship 
Ui={2/(N-2)*(N-1).sup.i+1 -N/(N-2)}*T is determined. Also, because the 
final transmission short pausing period Xsn is {2/(N-2)*(N-1).sup.N 
-N/(N-2)}*T, the final transmission long pausing period Xdn is set to 
{2/(N-2)*(N-1).sup.N -N/(N-2)}*T. Because the final signal grouping period 
Un is {2/(N-2)*(N-1).sup.N+1 -N/(N-2)}*T, the signal transmission cycle C 
is set to {2N/(N-2)*(N-1).sup.N -2N/(N-2)}*T. In this case, because of the 
i-th signal grouping period Ui={2/(N-2)*(N-1).sup.i+1 -N/(N-2)}*T, the 
i-th transmission long pausing period Xdi={2N/(N-2)*(N-1).sup.N 
-2/(N-2)*(N-1).sup.i+1 -N/(N-2)}*T is placed after the i-th signal 
grouping period Ui for each signal transmission cycle C. 
Also, in cases of N=2, Xs1=T, Xs2=3T, Xd2=3T, C=8T and Xd1=5T are set. 
Accordingly, there is no probability that all N signals transmitted from 
one transmitting unit simultaneously overlaps with other signals 
transmitted from the other transmitting units, and one or more signals 
transmitted from one transmitting unit is reliably received by a receiving 
unit without overlapping with any of other signals transmitted from the 
other transmitting units. That is, because one signal not overlapping with 
any other signal is transmitted to the receiving unit for each signal 
transmission cycle C, data indicated by a series of signals in a series of 
signal transmission cycles C can be reliably transmitted from each 
transmitting unit to the receiving unit. 
Also, because a plurality of signals Si is transmitted from each 
transmitting unit TUi at a regular frequency Xsi+T and the transmission of 
the signals Si is stopped for a regular transmission long pausing period 
Xdi, the transmitting unit and the receiving unit can be simplified. 
Also, because the method for transmitting signals from a plurality of 
transmitting units and receiving the signals in a receiving unit can be 
applied for a one-way communication, the transmitting unit and the 
receiving unit can be moreover simplified, and a small sized signal 
transmitting and receiving system can be manufactured at a low cost. 
In cases where the signal transmitting period T is equal to 10 msec, the 
signal transmission cycle C is 180 msec when two transmitting units are 
used, the signal transmission cycle C is 420 msec when three transmitting 
units are used, and the signal transmission cycle C is 900 msec when four 
transmitting units are used. 
In this embodiment, the transmission short pausing periods Xsi are set to 
satisfy the relationship Xsi=(2.sup.i+1 -3)*T. However, it is applicable 
that the transmission short pausing periods Xsi be set to satisfy the 
relationship Xsi&gt;(2.sup.i+ -3)*T. 
Also, three transmitted units are used. However, the number of transmitted 
units is not limited. 
Also, the periods Ui, Xsi, Xdi and the cycle C are determined to minimize 
the cycle C. However, it is applicable that the periods Ui, Xsi, Xdi and 
the cycle C be lengthened. 
Also, N signals are transmitted from each transmitting unit in cases where 
the number of transmitting units is N. However, it is applicable that a 
plurality of signals more than N be transmitted from each transmitting 
unit in cases where the number of transmitting units is N. 
Also, N types of signals transmitted from N transmitting units are received 
in a receiving unit. However, it is applicable that N receiving units be 
prepared and each type of signals transmitted from one transmitting unit 
be received in a corresponding receiving unit. 
Having illustrated and described the principles of the present invention in 
a preferred embodiment thereof, it should be readily apparent to those 
skilled in the art that the invention can be modified in arrangement and 
detail without departing from such principles. We claim all modifications 
coming within the spirit and scope of the accompanying claims.