Spread spectrum meter reading system utilizing low-speed/high-power frequency hopping

• US 7,283,580 B2
• Filed: 07/23/2001
• Issued: 10/16/2007
• Est. Priority Date: 07/21/2000
• Status: Expired due to Fees

• Current Assignee: Itron, Inc.
• Original Assignee: Itron, Inc.
• Inventors: Cumeralto, Scott, MacConnell, John
• Primary Examiner(s): TRAN, KHANH C
• Application Number:
  US09/911,840
• Publication Number:
  US 20020109607A1
• Time in Patent Office: 2,276 Days
• Field of Search: 375/132, 375/135, 375/136, 375/140, 375/137, 375/134, 340/870.02, 340/870.03, 340/870.11, 340/870.39, 340/870.18, 340/825.39, 340/825.43, 340/825.36
• US Class Current: 375/137
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 2203/5408 using protocols
• CPC Class Codes: H04B 2203/5425 improving S/N by matching impedance, noise reduction, gain control
• CPC Class Codes: H04B 2203/5433 Remote metering
• CPC Class Codes: H04B 2203/5441 Wireless systems or telephone
• CPC Class Codes: H04B 2203/547 via DC power distribution
• CPC Class Codes: H04B 2203/5479 using repeaters
• CPC Class Codes: H04B 2203/5491 using filtering and bypassing
• CPC Class Codes: H04B 3/36 Repeater circuits H04B3/58 takes precedence
• CPC Class Codes: H04B 3/546 Combination of signalling, telemetering, protection circuits for remote indication of supply or distribution network condition H02J13/00
• CPC Class Codes: H04Q 2209/40 using a wireless architecture
• CPC Class Codes: H04Q 2209/50 using a mobile data collecting device, e.g. walk by or drive by
• CPC Class Codes: H04Q 2209/60 for transmitting utility meters data, i.e. transmission of data from the reader of the utility meter
• CPC Class Codes: H04Q 2209/826 where the data is sent periodically
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A spread spectrum meter reading system enables the use of high power frequency hopping spread spectrum (HPSS) transmissions at both the encoder transmitter and repeater levels of the meter reading system. A plurality of end point encoder transmitter devices are each connected to a utility meter and transmit high power FHSS signals containing at least metering data for the corresponding utility meter. A plurality of intermediate transceiver units that are fewer in number than the number of end point encoder transmitter devices both receives and retransmits the high power FHSS signals. A base station includes a receiver that receives the high power FHSS signals. Preferably, the base station can receive the high power FHSS signals from both the encoder transmitter devices and the intermediate transceiver units and the intermediate transceiver units aggregates metering data from multiple encoder transmitter devices prior to block retransmission of the metering data to the base station. Preferably, the high power FHSS signals are transmitted at a maximum hopping rate of at least one minute per hop to reduce power consumption and increase battery life of the devices.

Claims

1. In an automatic meter reading (AMR) system comprising a plurality of utility meter end point modules that generate and transmit utility consumption data, and at least one AMR system receiver configured to receive consumption data transmitted by the end point modules by way of frequency hopping spread spectrum transmission, a method of communicating between a first end point module and the receiver, the method comprising:

maintaining, at the receiver, transmission profile information for the first end point module that represents at least a frequency hopping pattern used by the first end point module;

transmitting, by the first end point module, a first message, wherein the first message includes an identifier of the first end point module;

receiving, by the receiver, the first message;

determining, by the receiver, an identity of the first end point module based on the identifier of the first message to obtain a first determined identity;

determining, by the receiver, frequency hopping information associated with a future second transmission by the first end point module based on the first determined identity of the first end point module to obtain a first set of determined frequency hopping information;

predicting, by the receiver, whether the future second transmission will be unsuccessful based on the first set of determined frequency hopping information; and

responding to a predicted unsuccessful future second transmission by adjusting the communicating between the first end point module and the receiver.

2. The method of claim 1, further comprising:

transmitting, by a second end point module, a third message, wherein the third message includes an identifier of the second end point module;

receiving, by the receiver, the third message;

determining, by the receiver, an identity of the second end point module based on the identifier of the third message to obtain a second determined identity;

and

determining, by the receiver, frequency hopping information associated with a

future fourth transmission by the second end point module based on the

determined second identity of the second end point module to obtain second set of determined frequency hopping information;

wherein the step of predicting whether the future second transmission will be unsuccessful includes predicting whether any transmission collision will

occur between the future second transmission by the first end point module, and

the future fourth transmission by the second end point module.

3. In an automatic meter reading (AMR) system comprising a plurality of utility meter end point modules that generate and transmit utility consumption data messages, and at least one AMR system reader configured to receive consumption data messages transmitted by the end point modules, a method of operating a first reader, the method comprising:

determining a message arrival time for a future first message to be transmitted by a specific end point module;

predicting, by the first reader, whether the first message will be successfully communicated; and

adjusting reception activity of the first reader according to a result of the predicting step.

4. The method of claim 3, wherein the step of determining is based on an end point module message arrival list stored in the reader.

5. The method of claim 3, comprising:

transmitting the first message by a first end point module on a first frequency hopping spread spectrum (FHSS) channel; and

prior to the step of transmitting, determining, by the first reader, that the first message will be arrive on the first FHSS channel.

6. The method of claim 3, further comprising:

initializing the first reader, including establishing logic for handling any missed end point module messages.

7. An automatic meter reading (AMR) system receiver for receiving radio transmissions from a plurality of utility meter end point modules that generate and transmit utility consumption data by way of frequency hopping spread spectrum transmission, the AMR system receiver comprising:

a radio receiver; and

a controller programmed to;

maintain transmission profile information for ones of the plurality of end point modules, the transmission profile representing at least a frequency hopping pattern used by at least a first end point module;

operate the radio receiver to engage in radio communications with the first end point module, wherein the radio communications include a first message originated by the first end point module that includes an identifier of the first end point module;

determine an identity of the first end point module based on the identifier of the first message to obtain a first determined identity;

determine frequency hopping information associated with a future second transmission by the first end point module based on the first determined identity of the first end point module to obtain a first set of determined frequency hopping information;

predict whether the future second transmission will be unsuccessful based on the first set of determined frequency hopping information; and

respond to a predicted unsuccessful future second transmission by adjusting the radio communications with first end point module.

8. The AMR system receiver of claim 7, wherein the AMR system receiver is of a type selected from the group consisting of:

a repeater, and a base unit.

9. An automatic meter reading (AMR) system receiver for receiving radio transmissions from a plurality of utility meter end point modules that generate and transmit utility consumption data by way of frequency hopping spread spectrum transmission, the AMR system receiver comprising:

a radio receiver; and

a controller programmed to;

determine an arrival time for a future first transmission to be transmitted by a specific end point module;

produce a prediction of whether the first message will be successfully communicated; and

adjust operation of the receiver according to the prediction.

10. The AMR system receiver of claim 9, wherein the AMR system receiver is of a type selected from the group consisting of:

a repeater, and a base unit.

11. The AMR system receiver of claim 9, wherein the controller maintains an endpoint module transmission arrival list.

12. The AMR system receiver of claim 9, wherein the controller is configured with logic for handling any missed end point module transmissions.