Wireless alarm system
First Claim
Patent Images
1. A remote power meter monitoring system, comprising:
- a multiplicity of radio frequency transmit-only devices configured to transmit information, each radio frequency transmit-only device comprising,a timer comprising a memory that holds a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory,a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, anda retransmission means for redundantly transmitting said information a predetermined number of times;
at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits;
at least two receivers each capable of configuration to receive said transmitted information, and validation of said information based on said identification address and said error detection code bits contained in said transmitted information said receivers providing redundant reception of said transmitted information; and
a monitoring means for monitoring said information as received and validated by at least one of said receivers.
23 Assignments
0 Petitions
Accused Products
Abstract
A remote power meter monitoring system using spread spectrum transmitters, fast frequency shift keying, spread spectrum receivers and a computer. The spread spectrum transmitter uses a chip code generator, preamble register, address register data register and oscillator coupled to a microprocessor to transmit information in a direct sequence spread spectrum signal. The spread spectrum receiver acquires synchronization of the spread spectrum signal using a microprocessor to despread and detect the transmitted information, which relates to data from a power meter.
-
Citations
39 Claims
-
1. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information, each radio frequency transmit-only device comprising, a timer comprising a memory that holds a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, and a retransmission means for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each capable of configuration to receive said transmitted information, and validation of said information based on said identification address and said error detection code bits contained in said transmitted information said receivers providing redundant reception of said transmitted information; and a monitoring means for monitoring said information as received and validated by at least one of said receivers. - View Dependent Claims (7, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
2. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, each radio frequency transmit-only device comprising, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a timer configured to hold a pseudo random time interval value, said timer configured to initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value, a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, a retransmission means for redundantly transmitting said information a predetermined number of times, and a wake-up circuit configured to initiate said crystal oscillator and said processor in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said processor in a reduced current state between transmissions; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each capable of configuration to receive said transmitted information, and validation of said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information; and a monitoring means for monitoring said information as received and validated by at least one of said receivers.
-
-
3. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence used to produce said spread spectrum signal, each radio frequency transmit-only device comprising, a timer comprising a memory for holding a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, and a retransmission means for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each configurable to receive said transmitted information, and configurable to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said at least two receivers providing redundant reception of said transmitted information, said at least two receivers configured to establish chip code synchronization to said direct sequence spread spectrum signal using said preamble; and a monitoring means for monitoring said information as received and validated by at least one of said receivers. - View Dependent Claims (8)
-
-
4. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence plus approximately five bit times, each radio frequency transmit-only device comprising, a timer comprising a memory for holding a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, and a retransmission means for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each configurable to receive said transmitted information, and configurable to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information, said receivers configured to establish chip code lock and fine chip code synchronization using said preamble; and a monitoring means for monitoring said information as received and validated by at least one of said receivers.
-
-
5. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is less than n bit times, where n equals a number of chips in a chip code sequence, each radio frequency transmit-only device comprising, a timer comprising a memory for holding a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a pseudo-randomization means for generating and loading said pseudo random time interval value into said timer, and a retransmission means for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each configurable to receive said transmitted information, and configurable to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information, said receivers comprising respective parallel correlation means for establishing chip code synchronization using said preamble; and a monitoring means for monitoring said information as received and validated by at least one of said receivers.
-
-
6. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, each radio frequency transmit-only device comprising, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a timer configured to delay transmission of said information by a predetermined delay after said expiration of said time duration so as to allow for crystal stabilization, transmit carrier frequency stabilization and chip code timing generation stabilization, a retransmission means for redundantly transmitting said information a predetermined number of times, and a wake-up circuit configured to initiate said crystal oscillator and said processor in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said processor in a reduced current state between transmissions; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each of which being configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information; and a monitoring means for monitoring said information as received and validated by at least one of said receivers. - View Dependent Claims (23)
-
-
9. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configurable to transmit information in a message, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, and a pseudo-randomization means for randomizing the time duration between transmissions of said message, a retransmission means for redundantly transmitting said message a predetermined number of times, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a carrier generator mechanism configured to generate a carrier on which said information to be transmitted is modulated, and a wake-up circuit configured to initiate said crystal oscillator and said carrier generator mechanism in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said carrier generator mechanism in a reduced current state between transmissions, said information being transmitted after a predetermined delay with respect to when said crystal oscillator and said carrier generator mechanism are placed in said respective active states so as to allow for stabilization in said carrier generator mechanism and said crystal oscillator prior to information transmission; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; a receiver configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information; and a monitoring means for monitoring said information as received and validated by said receiver.
-
-
10. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, each radio frequency transmit-only device comprising, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a timer configured to initiate transmission of said information after expiration of a time duration, a retransmission means for redundantly transmitting said information a predetermined number of times, a pseudo-randomization means for randomizing the time interval between redundant transmissions, a carrier generator mechanism configured to generate a carrier on which said information to be transmitted is modulated, and a wake-up circuit configured to initiate said crystal oscillator and said carrier generator mechanism in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said carrier generator mechanism in a reduced current state between transmissions, said information being transmitted after a predetermined delay with respect to when said crystal oscillator and said carrier generator mechanism are placed in said respective active states so as to allow for stabilization in said carrier generator mechanism and said crystal oscillator prior to information transmission; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; a receiver configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information; and a monitoring means for monitoring said information as received and validated by said receiver. - View Dependent Claims (24)
-
-
11. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence used to produce said spread spectrum signal, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, a retransmission means for redundantly transmitting said information a predetermined number of times, a pseudo-randomization means for randomizing the time interval between redundant transmissions, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a carrier generator mechanism configured to generate a carrier on which said information to be transmitted is modulated, and a wake-up circuit configured to initiate said crystal oscillator and said carrier generator mechanism in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said carrier generator mechanism in a reduced current state between transmissions, said information being transmitted after a predetermined delay with respect to when said crystal oscillator and said carrier generator mechanism are placed in said respective active states so as to allow for stabilization in said carrier generator mechanism and said crystal oscillator prior to information transmission; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; a receiver configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receiver configured to establish chip code synchronization to said direct sequence spread spectrum signal using said preamble; and a monitoring means for monitoring said information as received and validated by said receiver.
-
-
12. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence plus approximately five bit times, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, a retransmission means for redundantly transmitting said information a predetermined number of times, a pseudo-randomization means for randomizing the time interval between redundant transmissions, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a carrier generator mechanism configured to generate a carrier on which said information to be transmitted is modulated, and a wake-up circuit configured to initiate said crystal oscillator and said carrier generator mechanism in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said carrier generator mechanism in a reduced current state between transmissions, said information being transmitted after a predetermined delay with respect to when said crystal oscillator and said carrier generator mechanism are placed in said respective active states so as to allow for stabilization in said carrier generator mechanism and said crystal oscillator prior to information transmission; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; a receiver configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receiver configured to establish chip code lock and fine chip code synchronization using said preamble; and a monitoring means for monitoring said information as received and validated by said receiver.
-
-
13. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is less than n bit times, where n equals a number of chips in a chip code sequence, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, a retransmission means for redundantly transmitting said information a predetermined number of times, a pseudo-randomization means for randomizing the time interval between redundant transmissions, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing for said information generated by said processor, a carrier generator mechanism configured to generate a carrier on which said information to be transmitted is modulated, and a wake-up circuit configured to initiate said crystal oscillator and said carrier generator mechanism in respective active states upon expiration of said time duration so as to transmit said information, and configured to place said crystal oscillator and said carrier generator mechanism in a reduced current state between transmissions, said information being transmitted after a predetermined delay with respect to when said crystal oscillator and said carrier generator mechanism are placed in said respective active states so as to allow for stabilization in said carrier generator mechanism and said crystal oscillator prior to information transmission; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; a receiver configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receiver comprising respective parallel correlation means for establishing chip code synchronization using said preamble; and a monitoring means for monitoring said information as received and validated by said receiver.
-
-
25. A remote power meter monitoring method, comprising the steps of:
-
retrieving data from a sensing element; generating information containing the retrieved data, comprising, generating an identification address field for holding an identification address corresponding to a transmit-only device, and generating an error correction code; transmitting the generated information, redundantly at pseudo random intervals from said transmit-only device, comprising, loading a timer with a pseudo random time interval value, enabling, upon expiration of said pseudo random time interval value as timed by said timer, a crystal oscillator used to generate spread spectrum timing signals, a transmitter oscillator used to generate transmission signals, delaying information transmission for a predetermined time period, relative to said expiration of said pseudo random time interval value, to allow for stabilization of said crystal oscillator and said transmitter oscillator, transmitting a preamble portion of said information used for spread spectrum timing synchronization, said preamble having a length in bit times at least equal to a number of chips in a chip code sequence used in direct sequence spread spectrum format by said transmit-only device, transmitting the generated information in said direct sequence spread spectrum format based upon said chip code sequence and said spread spectrum timing signals at a predetermined frequency by said transmit-only device, disabling said crystal oscillator and said transmitter oscillator, so as to conserve power; repeating said step of transmitting said generated information redundantly after a pseudo random interval of time so as to provide information transmission redundancy; receiving the generated information by at least one receiver; validating the received information based on said identification address and said error correction code; transferring the validated information to a monitoring mechanism; and monitoring the received data in the validated information with the monitoring mechanism. - View Dependent Claims (26, 27, 28)
-
-
29. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, a random number generator configured to generate a pseudo random time interval value and to cause the time interval between transmissions to be pseudorandom, and a retransmission mechanism configured to retransmit said information a predetermined number of times; at least one sensing element configured to provide sensor data gathered therein to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information; and a monitoring apparatus that is configured to monitor said information as received and validated by at least one of said receivers. - View Dependent Claims (35, 36)
-
-
30. A remote power meter monitoring system, comprising:
-
a multiplicity radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, each radio frequency transmit-only device comprising, a processor configured to generate said information to be transmitted, a crystal oscillator configured to generate spread spectrum timing information for said information generated by said processor, a timer configured to hold a pseudo random time interval value and initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value, a random number generator mechanism that generates said pseudo random time interval value and loads said pseudo random time interval value into said timer, and a retransmission mechanism configured to cause said information to be retransmitted a predetermined number of times, and a wake-up circuit configured to initiate said crystal oscillator and said processor in respective active states upon expiration of said time duration so as to transmit said information when in said respective active states, and configured to place said crystal oscillator and said processor in a reduced current state between transmission times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising, a data field that holds said sensor data, an address field that holds an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and an error field that holds error detection code bits; at least two receivers each configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information; and a monitoring apparatus that is configured to monitor said information as received and validated by at least one of said receivers. - View Dependent Claims (34)
-
-
31. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence used to produce said spread spectrum signal, each radio frequency transmit-only device comprising, a timer configured to autonomously initiate transmission of said information after expiration of a time duration, a random number generator that generates a pseudo random time interval value and causes the time interval between transmissions to be pseudorandom, and a retransmission mechanism configured to cause said information to be retransmitted a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising, a data field that holds said sensor data, an address field that holds an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and an error field that holds error detection code bits;
at least two receivers each configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information, said receivers configured to establish chip code synchronization to said direct sequence spread spectrum signal using said preamble; anda monitoring apparatus that is configured to monitor said information as received and validated by at least one of said receivers. - View Dependent Claims (37, 38, 39)
-
-
32. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is at least equal in length to a number of chips in a chip code sequence plus approximately five bit times, each radio frequency transmit-only device comprising, a timer comprising a memory that holds a pseudo random time interval value, and configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a random number generator configured to generate said pseudo random time interval value and load said pseudo random time interval value into said timer, and a retransmission device for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising said sensor data, an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and error detection code bits; at least two receivers each configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information, said receivers configured to establish chip code lock and fine chip code synchronization using said preamble; and a monitoring device for monitoring said information as received and validated by at least one of said receivers.
-
-
33. A remote power meter monitoring system, comprising:
-
a multiplicity of radio frequency transmit-only devices configured to transmit information in a direct sequence spread spectrum signal at plural frequencies, said information comprising a first field comprising a preamble configured to establish chip code timing synchronization and a second field comprising data, said first field being transmitted prior to said second field, said preamble having a length measured in bit times that is less than n bit times, where n equals a number of chips in a chip code sequence, each radio frequency transmit-only device comprising, a timer comprising a memory that holds a pseudo random time interval value, said timer configured to autonomously initiate transmission of said information after expiration of a time duration corresponding to said pseudo random time interval value held in said memory, a random number generator configured to generate said pseudo random time interval value and for loading said pseudo random time interval value into said timer, and a retransmission device for redundantly transmitting said information a predetermined number of times; at least one sensing element configured to provide sensor data to said radio frequency transmit-only device, said transmitted information comprising, a data field that holds said sensor data, an address field that holds an identification address being assigned to said radio frequency transmit-only device to which the sensor data is provided, and an error field that holds error detection code bits; at least two receivers each configured to receive said transmitted information, and configured to validate said information based on said identification address and said error detection code bits contained in said transmitted information, said receivers providing redundant reception of said transmitted information, said receivers comprising respective parallel correlation mechanisms that establish chip code synchronization using said preamble; and a monitoring device for monitoring said information as received and validated by at least one of said receivers.
-
Specification