Note: Descriptions are shown in the official language in which they were submitted.
A SYSTEM FOR PRODUCIN~ S2
AN OPERATING SIGNAL
The present invention relates to a system for
producing a signal in a circuit incorporated in a unit
of property, hereinaf-ter referred -to as unit, such as
a bank or ofEice building, said system including an
alarm centre having a data processor and a random
signal generator for transmitting control signals, and
a terminal in the form of a mobile signal unit arranged
to produce a characteristic code signal.
The system is primarily intended for security
companies, where the data processor, together with
auxiliary equipment, is installed in the company's
alarm centre, and the terminal, which can be made very
light, is carried by the guard. In systems of -this
kind known hitherto, there is no direct relationship
between the data processor and the -terminal. The
data processor has mainly been used for registering
random code signals sent to the unit and for regis-
tering reply signals from said unit, while the
terminal has been used to send directly to the unit
a characteristic code which gives the guard entry
to the unit, by activating, for example, a lock
circuit in a lock-opening mode through the code
signal.
The prime object of the invention is to uti-
lize a data processor, random signal generator and
terminal in an integrated system which firs-tly affords
optimum security and secondly, if so desired, enables
3~
measures taken by t~e guard or some other person
equipped with a terminal, and the result of -these
measures, to be verified.
This optimum security is achieved by pro-
ducing an operating signal for entry to -the uni-t,
or for ac-tivating a device in said uni-t, by means
of a random code signal which is simul-taneously
transmitted from the alarm centre to the unit and
-to the terminal, and also from the terminal to
the unit. Thus, the operating signal is obtained
solely as a reply to two identical random code
signals fed-in from t-~o mutually separate pieces
of equipment within one and the same time interval.
The random code signal is preferably fed in by
means of a small hand-carried signal pen, arranged
to send the random code signal in the form of light
signals to a specific receiving location at, for
example, an entrance to a bank. This means that the
guard must position the signal pen against, or closely
adjacent an optical lens, for example, in a receiver,
which constitutes a good safeguard against an intru-
der feeding in the random code signal from the ter-
minal when, for example, overcoming the guard after
the guard has sent his signal alarm centre.
Verification of the steps taken by the guard
or the user, and the signals obtained is effected
through the arrangement of a memory store in the
terminal~ said memory store, for example, being read-
out upon completion of an inspection round by the
guard or upon completion of a working period, and
the con-tents of said store written onto a recording
sheet. In this way, the secw-ity company obtains proof
that the guard in their emplov has fulfilled his duty to
the client.
Thus, the present invention provides a system
for sending an operating signal to a circuit located in
a unit of propext~, the system including an alarm centre
provided with a data processo:r and a random signal generator
for transmitting control signals, and a terminal in the
form of a mobile signal uni~ arranged to transmit a char--
acteristic code signal, wherein the terminal includ~s a
code transmitter for electric signals with a stored unit
code characteristic of the unit; means for energizing the
code transmitter and transmitting the unit code and a terminal
code characteristic of the terminal to the alarm centre;
a signal receiving device in the alarm centre for trans-
mitting the received unit cocle to the data processor, which
is arranged to compare the received unit code with an iden-
tical unit code stored in the data processor -together
with the terminal code, and wherein when there is agreement
between the received and the stored unit code and the ter-
minal code to cause a random signal generator to transmit
a random code signal to a random-code-signal receiver-
transmitter in the terminal and to a code receiver in the
unit; a signal transmitting device which is connected to
the terminal and arranged to transmit from the random-code-
signal receiver-transmitter the random code signal received
- 3a -
by the terminal to the code receiver the code receiver being
arranged to compare the two received random code signals
in a comparison circuit and, when there is agreement between
the signals to produce the operating signal.
The drawing is a simplified view of an exemplary
embodiment oE a system according to the invention. The
guard, or other person, who is to use the system to guard
a unit, or to obtain entry thereinto, such as a factory,
a bank, an alarm system or the li~e has been provided with
a portable terminal 1 and a radio transmitter and receiver
2. The terminal 1 incorporates a push-button board 3 by
means of which the guard can enter an allotted personal
number or a code number given to him when leaving the ter-
minal. The push-button board 3 can be provided with a
separate button or key 4 for generating an implementation
signal. In the illustrated embodiment, the terminal com-
prises a clock 5, suitably a quartz clock, driven by
batteries (not shown) arranged in the terminal, the batteries
also being used to drive the electronic circuits in the
terminal. The terminal 1 also incorporates a code trans-
mitter 6 which receives the cutput signal from the push-
button board 3 through a line ~9, and contains a code which
is fed in by the alarm centre 11 which has issued the ter-
minal, and which is unknown to the user of the terminal.
The code transmitter 6 contains a code number in binary
form for the unit or units t~ which the user of the terminal
has access, and the time expressed in day, month and
year, and preferably also in which time period, -the
user of the terminal can activate the aforementioned
device in said unit. The time period may comprise
one or more minutes, or a full day. In order to be
able -to give correct information in this case, the
clock 5 is arranged to produce signa:Ls relating to
the day, month, year and -the -time of day. The sig-
nals produced by -the clock 5 are fed through a line
7 to the code transmitter 6, either continuously or
after pressing the button 4, and the code transmi-tter
compares the time signals with the programmed time
signal and is blocked when a cGmparison shows that
-the terminal 1 is used outside the permitted time
period. The terminal 1 is also provided with a
random-code signal receiver and random-code signal
transmitter 8 and a registering memory store 9, in
which the steps taken and the -time at which the
steps were taken etc. are registered, and which can
be coupled to a data processing sys-tem when the
duties of the attendant person have been carried
out, for writing out this information.
In the illustrated embodiment, the memory
store 9 is connected to the bank of push-buttons 3
by a line 17, and is opened, i.e. made available
for registration, immlediately the push-but-ton
board is activated, by entering the code number of
the user or by activating the implementation button
4. In this way, the code number of the user is
registered and also the -time at which the push-
bu-tton board or implemen-tation button 4 was activa-ted,
since~the clock 5 feeds its information into the
memory store -through a line 18.
The portable transmitter-receiver 2 carried
by -the user is connected to the output of the code
transmitter 6 through a line 40, and is adapted to
transmit code signals from the code transmitter 6
to a data processor 10 in -the centre- 11 which has
issued -the terminal 1 and inserted -the code in
the code transmitter 6 of the terminal. The signals
transmi-tted to the data 10 by means of the antenna
or aerial 12 are shown by the broken line 13. The
receiver part of the transmitter-receiver 2 is
arranged to receive wireless radio signals from a
radio transmitter 24 in a random code signal genera-
tor 1~ connected to the data processor 10, as indi-
cated by the broken line 15, and these signals are
transmitted to the random-code-signal receIver-
transmitter 8 through a line 16. Informa-tion re-
ceived in the random-code-signal receiver-transmitter
8 is transrnitted through a line 19 to the memory
store 9, which also received, through a line 20, and
stores code signal information transmitted from the
code transmitter 6 to the transmitter part of the
-transmitter-receiver 2.
The central data processor 10 is arranged to
receive by means of a radio receiver 21 the output
signals from the transmitter part of the transmitter- ¦
receiver 2, and to compare the signals with stored
information which is identical with -the information
in the code transmitter 6 combined with the code
entered by the user of the terminal 1 through the
push-button board 3. If the information stored in
the data processor 10 coincides with -the instruc-
tions or information in -the code transmitter 6,
the data processor 10 will send, through line 22,
an opening signal to the random signal generator
14, which then transmits .a completely randomly
selec-ted code signal on the output line 23, and
in addition over the radio transmitter 24 the
same randomly selected signal which is received by
the receiver part of the -transmitter-receiver 2,
which sends the signal further over line 16 to
the random-code signal receiver-transmitter 8.
Should the information contained in -the data
processor 10 not coincide with the signal ob-
tained from the transmitter-receiver 2, an alarm
signal can be sent over a line 25, this alarm
signal being arranged, for example, to activate
an optical or acoustic device (not shown) in the
alarm centre.
This lack of agreement between the signal
from the code transmitter 6 and the code stored
in the data processor 10 may be caused by the
guard entering the wrong code number into the
push-button board 3, or by the guard attempting
to approach the unit at the wrong time etc, or
by the terminal 1 being used by an unauthorized
person. It is assumed here that there is agree-
ment between said signal and said code and that
consequently the random code generator, which may
be of any known type, has transmitted a signal
through the line 23 and -the radio transmitter 24.
The random code signal is received in a code re-
ceiver 26 in the unit 27 to be reached by the
guard, the user of the terminal 1, with the guard
being located at a check point outside or wi-thin
the uni-t 27. The check point is provided with an
optical receiver-transmitter 28, which is arranged
-to receive signals from an optical transmi-tter--
receiver 29, which in the illustrated embodiment
has the form of a rod or pen manipulated by the
guard. As beforementioned, the signals produced
by the random code generator 14 are received by
the transmi-tter-receiver 2 coupled to the terminal
1, and are fed into the random code receiver-
transmitter 8, from where the signals are -trans-
mi-tted further to the optical transmitter-receiver
29, via a flexible cable 30. The pen 29 may also
be incorporated in the housing or casing of the
terminal 1, in which casè the whole of the terminal
is moved towards the optical receiver-transmitter 28.
The transmitter-receiver 29, which is of a kind
known per se, is provided, for example, with a first
light diode, which is pulsed with the random code
signals and transmi-ts light pulses to the optical
receiver-transmitter 28, which converts these light
pulses into corresponding electric pulses, i.e. to
the code transmitted by the random signal generator
14. The receiver 28 transmits the random signal
pulses -to the code receiver 26 through a line 30,
said receiver also receiving the pulses directly
from the random signal generator 14, as before-
mentioned. The -two signals, i.e. the signals from
the random signal generator 14 and from the re-
ceiver--transmit-ter 28 are sent from -the code re-
ceiver 26, which contains a comparison circuit 31
s~
in which the signals are compared. Since the signals
obtained on the line 23 are the same as those obtained
on the ]ine 30, it is naturally possible to establish
agreement, and an operating or clear signal is trans-
mitted from the comparison circuit through line 32.
This operating signal is transmi-t-ted through line 33
to the -transmitter part of the receiver-transmitter
28, in which a second light diode (not shown) converts
-the electrical pulses to light pulses, which are re-
ceived by a light-sensitive element in the transmitter-
receiver 29, and are transmitted in the form of elec-
trical pulses to the memory store 9 through cable 30.
In the examplary embodiment of the invention, the
memory store 9 is arranged to store the check number
of the guard, the time at which an at-tempt to reach
the data processor 10 has been made, the random code
signal from the radio transmitter 24 of the random
signal generator, the signal transmi-tted by -the code
transmitter 6 to the data processor 10, and the
operating signal from the transmitter part of the
receiver-transmitter 2&. By registering this in-
formation there is ob-tained perfect verification of
those signals transmitted and leaving the alarm
centre 11 and the unit 27 respectively. As will be
understood, however, certain signals can be excluded,
for example -the registration of the random signal
generator 14, and that other signals can be included,
as hereinafter described.
It has been mentioned that the code transmit-ter
6 is arranged to transmit -the code over an extremely
limited time period, or preferably only once for each
activation of the push-button board, and that the
random-code-signal receiver-transmit~er 8 is
arranged to transmit the random code signal at the
same -time as, or practically a-t the same time as,
it is genera-ted by the random signal generator 14,
which in turn is preferably arranged to transmit
the signal only once. In prac-tice, this means -that
the transmit-ter-receiver 29 must be in co-action
with the receiver-transmi-t-ter 28 a-t the same time
as, or immediately after the signal has left the
code transmitter 6. If this co-action between the
transmitter-receiver 29 and the receiver--transmitter
28 has not been established, the random code signal
from the terminal 1 will not reach the signal
comparison circuit 31 at the same time as the signal
is received through the line 23, and consequently
an error signal will be sent from the signal com-
parison circui-t through a line 34, this error
signal being registered in -the memory store 9. As
will be understood, the operating signal will no-t
be transmitted.
The operating signal on line 32 is transmi-tted
to a control circuit incorporated, for example, in a
factory-door locking device 35, a control circuit 36
arranged to initiate the sequence of even-ts in a
process in an unmanned factory, a control circuit 37
which disconnects an internal alarm system in the
unit 27, so that the guard is able to move freely,
etc. The complet~ion of the requested function can
also be registered in the memory store 9. Thus,
when the locking device has been opened, the ccntrol
- 10
circuit 35 can send a signal over line 38, -this
signal being -transmitted to the memory ~tore ~ in
a manner not further shown. The signal on line 38
may also be transmitted to the central data pro-
cessor 10 over a signal link (not shown), for
example a fixed signal line or a radio link, -to
be registered -there. In this case, the data pro-
cessor 10 is suitably arranged to compare -this
signal with a programme and to transmi-t an alarm
signal when said signal is excluded. In certain
cases, this signal is of extreme importance, for
example when a valve in a process system is to be
activa-ted at a given point of time in order for
the process -to proceed normally. Such a signal
can also give an indica-tion that the guard is
carrying out his work in a normal manner during
his working period.
In the aforegoing it has been assumed that
full security can be achieved by sending the
random code signal from the alarm centre 11 and
the terminal 11 to the unit 27. In order to
eliminate the possibility of an operating signal
being produced by sending a false random code
signal to -the unit 27 over line 23, and an
identical false random code signal being fed
into the receiver 28, it is highly advanta~eous to
combine the random code signal sent from the
alarm centre 11 with -the unit code inserted in
the code -transmi-tter ~, this unit code being
unknown to the user of -the terminal and unique
for the unit or units in question. As pre-
viously described, this unit code is sent from
the terminal 1 and received by the data processor
10, from where it is transmitted by the data pro-
cessor together with the random code signal and
received by the unit and by the terminal. The
unit code signal, which is received by the unit,
precedes-the random code signal and has the func-
tion of "opening" the comparison circuit 31 for
receivin~ and comparing the two random ccde sig-
nals. The unit code signal can be fed to the
unit 27 from the alarm centre 11 and/or from the
terminal 1 and prevents an operating signal being
generated by unauthorized signal transmission.
In the case of unauthorized signal transmission,
the signal on -the line 38 is utilized~ this signal
being transmitted over a line or radio lin~ (not
shown) to tlle data processor, which when receiving
the signal discovers that there is no unit signal
in the programme for the unit in question, and
therewith gives an alarm. In order for the unit
to be identified in this case, the signal on the
line 38 must contain a code which is characteristic
of the unit in question and which can be incorporated
in the clear signal on the line 32.
The described embodiment of -the invention,
and also the various circuits, devices and arrange-
ments incorporated in said embodiment, can be
modified in a number of ways. For e~ample~ the
signals can be transmitted between the terminal 1
and the alarm centre 11 galvanically, in which case
there is provided between the unit 27 and the
alarm centre 11 a signal line on which the guard
-12-
couples in the terminal 1. It is a.lso possible
to use a radio-link connection between the alarm
centre 11 and the uni-t 27, instead of the described
gulvanic connection.
Signals can be transmi-tted between the
termi.nal and the unit 27 in a manner other than via
the optically operating arrangement 28, 29. For
example, an electric plug arranged to co-act with
a corresponding electric contact on the cable 30
can be mounted on or adjacent the unit~ so as to
produce a gulvanic connection between the cable 30
and the comparison circuit 31. This connection
can also be produced magnetically or inductively
if so desired. It is preferred, however, tc use
the described optical arrangement, since, among
other things, this means that the only visible
and accessible element on the unit will comprise
a glass-covered window of very small dimensions,
which is difficult to force.
It is also possible to exclude the manual
inser-tion of the personal code number of -the guard
or user, in which case the push-button board 3
can be reduced to a single means, for example the
button 4, for energising the code transmitter 6
and transmitting a signal to the data processor 10
together with a code characteristic of the terminal
1. As will also be understood, the described
-transmitter-receiver 2 can be incorporated as an
integral part of the terminal 1.
~ en the terminal is carried by a guard
whose duty is to guard a plurality of mutually
- 13 -
independant units, which -thus have mutually differen-t
unit codes, the code transmitter of the terminal will
contain these different unit codes, which are made
available for transmission to the alarm centre with-
in the time intervals over which -the guard is in-
s-truc-ted -to visi-t respec-tive uni-ts in accordance with
a g~ven programme.
A positive signall;ng is obtained from -the
security aspect by generating the random signal code
directly from an alarm centre and transmitting said
code to the unit and to the terminal. The terminal
is preferably provided with a memory store for
enabling the steps taken by the guard at differen-t
times, and the result of these steps etc., -to be
verified at any point in time whatsoever, it being
possible to use the memory store for registering,
for example, a bar code or magnetic code, which is
read-off by means of the optic pen 29 or by means
of a magnetic-code reader respectively. These bar
codes are placed at different locations within the
unit and regis-tra-tion of the code indicates that
the guard has completed a given inspection round
within the unit. Such a bar code can also be
arranged on the inside of the door of a safe or
the like~ and if the door is opened or unlocked
the security company is able to prove that in-
ternal security rules have not been complied with.
