JP3346578B2 - Automatic meter reading data communication system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to an automatic meter reading data communication system. More specifically, the present invention provides a utility (ut
ility: a utility / utility company such as electricity, gas, water, etc. attached to a meter, and a commodity (commodity: electricity,
An integrated device that transmits usage data and other information to a remote communication device via a two-way wireless local area network (LAN), such as gas, water, etc.
Transmit to the utility service provider over the directional fixed operator's wide area network (WAN).

Traditionally, commodity usage is determined by utility companies using meters that monitor subscriber consumption. Utility service providers typically determine subscriber consumption by dispatching service personnel to each meter location and manually recording the information displayed on the meter dial. The results of the manual reading are input to a computer, which processes the information and outputs a bill for the subscriber. It is often very difficult for service personnel to get close to the meter. If access to the meter is not possible, billing is based on reading the estimate. These predictive charges often lead to customer complaints.

It is very labor intensive, inefficient, and very expensive for service technicians to read the meters visually. Therefore, using modern technology to reduce operating costs and increasing efficiency by reducing the need for on-the-fly meter reading is a strong concern for utility companies in that area. .

Many attempts have been made in recent years to develop automatic meter reading systems for water, gas and electric meters to avoid the high costs of on-site meter reading. However, most of these prior art systems have had little success.

In an effort to simplify meter reading, various types of devices have been attached to utility meters. These devices were developed to transmit commodity usage data over a communication link to a centralized service center or utility. These communication links included telephone lines, power lines, or radio frequency (RF) links.

The use of existing telephone and power lines to convey commodity usage data to utilities has faced significant technical difficulties. In a telephone line system, meter data may interfere with the subscriber's normal telephone line operation and may require cooperation between telephone companies and utility companies for shared use of telephone lines. Telephone line communication links may also require a hard-wired connection between the meter and the main telephone line, which increases installation costs. Power line carrier (PLC) communication links over existing power lines may also require a hard-wired connection between the meter and the main power line. Another disadvantage of PLC systems is that data can be lost due to interference on the power line.

Meters that can be read remotely are being developed. Such meters are configured as transponders,
Includes a wireless transmitter for transmitting data to the utility. These prior art systems required the meter to be polled by the data interrogator at regular intervals. The data interrogator may be provided on a mobile unit that travels nearby, including a portable hand-held unit carried by a service person. Alternatively, the data transmitter is provided at a centrally located site. If the meter is interrogated by an RF signal from a data transmitter, the meter responds by sending a signal encoded with the meter reading and other information requested. The communication is not started from the meter.

However, such prior art has drawbacks.
The first disadvantage is that the devices installed in the meter typically have a very low power output and a small transmitter with a very short transmission range. This requires that the interrogation unit be close to the meter. Another disadvantage is that devices attached to the meter must be polled periodically by a data interrogator. Devices attached to the meter cannot disclose communications. Mobile and handheld data interrogators have limited value because it is still necessary for service technicians to roam around neighborhoods and businesses to read the meter remotely. It simply avoids the need to enter homes or other buildings to read the meter. Systems that use fixed-location data interrogators also have the disadvantage of requiring low power output from the device attached to the meter and polling by the data interrogator to initiate communication.

Thus, although automatic meter reading systems are known in the prior art, currently available automatic meter reading systems have several disadvantages, such as low operating range and low communication reliability. Accordingly, it would be particularly desirable to provide an automated meter reading system that provides reliable communication of information from the meter to the utility, avoiding the need for utility service personnel to manually read the meter.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a reliable automatic meter reading data communication system that extends from commodity meters to utility service providers.

It is another object of the present invention to provide an interface management unit with a register head of an existing commodity meter that provides commodity usage data to a remote gateway node via a two-way radio spread spectrum local area network. .

It is a further object of the present invention to provide a gateway for receiving commodity usage data from an interface management unit and transmitting the data to a utility service provider via a commercially available fixed-carrier wide area network. Is to provide nodes.

Yet another object of the present invention is to perform data requests from utilities, pre-planned and scheduled meter readings, and to generate spontaneous fraud and alarm messages from interface management units attached to commodity meters. To provide the necessary communication links for handling.

The present invention is an automatic meter reading data communication system that can be attached to commodity meters, such as water, gas and electricity meters, to collect and process data and to send the data to a utility service provider. It incorporates an interface management unit for transmitting from the meter to a remote gateway node. The interface management unit replaces the register head of the commodity meter using an adapter ring for retrofitting the interface management unit to an existing meter body for meters manufactured by a wide range of manufacturers. The interface management unit has a digital encoder and a two-way wireless transceiver and automatically reads commodity usage based on utility requests or pre-programmed schedule readings. The interface management unit also monitors the status of the meter to determine fraud and alarm conditions.

The encoder and transceiver of the interface management unit consist of four main elements. These elements are
A management microcontroller, a communication microcontroller, a spread spectrum processor and an RF transceiver. The management microcontroller monitors and acquires commodity usage data from the meter. The management microcontroller also detects interrogation signals and presence from the gateway node. The communication microcontroller is connected to the management microcontroller and controls the internal and external communication functions of the interface management unit. The spread spectrum processor is connected to the communication microcontroller and enables the interface management unit to send and receive data using RF spread spectrum communication technology over a local area network. The RF transceiver is connected to the spread spectrum processor and the communication microcontroller, transmits commodity usage data from the meter, and receives interrogation signals from the gateway node.

The gateway node is located remotely from the interface management unit to complete the local area network. The gateway node also consists of four main elements. These elements include a wide area network interface module, an initialization processor,
A spread spectrum processor and an RF transceiver. The gateway node is responsible for providing interrogation signals to and receiving commodity usage data from the interface management unit for the local area network. However,
The gateway node also provides a link to the utility service provider via a commercially available stationary two-way telecommunications carrier wide area network.

The RF transceiver of the gateway node sends an interrogation signal from the utility or a pre-programmed signal for reading according to a schedule to the interface management unit, and returns the commodity usage data as a response from the interface management unit via the wide area network. Receive for transmission to the utility. A spread spectrum processor connects to the RF transceiver and enables the gateway node to transmit and receive data using spread spectrum communication technology. The WAN interface module is connected to the spread spectrum processor and transmits data to and from the utility service provider over the desired commercially available wide area network. Different WAN interface modules may be used in each of the different commercial wide-area networks desired. The initialization microcontroller is located between the interface module and the spread spectrum processor, and controls the operation of the spread spectrum processor and controls communication within the gateway node.

In another embodiment of the invention, a relay node is located in the local area network between the interface management unit and the gateway node to provide additional communication capabilities as needed. Therefore, if the gateway node is outside the RF communication range of the interface management unit,
And a relay node is required to retransmit the RF communication data from the interface management unit.

Meter reading, meter information management and network communication are all controlled by two-way system software pre-programmed on the interface management unit during manufacturing and installation and on the gateway node. The software configures the interface management unit to encode and manage input from a wide range of water, gas and electricity meters. The software allows the operator to easily change the serial number, read the meter automatically or on request, change the reported units of measurement,
System status can be monitored for reporting alarms or low battery conditions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an interface management unit of the present invention mounted on a water meter.

FIG. 2 is a perspective view of an adapter ring used to mount the interface management unit.

FIG. 3 is an exploded perspective view of the internal structure of the interface management unit.

 FIG. 4 is a front view of the gateway node.

FIG. 5A is a schematic diagram of an interface management unit for water, gas and electricity meters that connects with remote gateway nodes and utility service providers.

FIG. 5B connects with neighboring relay nodes, remote gateway nodes and utility service providers.
FIG. 2 is a schematic diagram of an interface management unit for water, gas and electricity meters.

FIG. 6A is a flow diagram of the automatic meter reading data communication system.

FIG. 6B is a flowchart of another automatic meter reading data communication system.

FIG. 7 is a block diagram of the interface management unit circuit.

FIG. 8 is a block diagram of the RF transmitters of the interface management unit, the relay node, and the gateway node.

FIG. 9 is a block diagram of a frequency synthesizer portion of the RF transmitter in FIG.

 FIG. 10 is a block diagram of the gateway node circuit.

FIG. 11A is a flowchart showing the operation of the interface management unit in power management and communication.

 FIG. 11B is a continuation of the flowchart in FIG. 11A.

 FIG. 11C is a continuation of the flowchart in FIG. 11B.

FIG. 12 is a flowchart of the initial setting of the interface management unit.

FIG. 13 is a flowchart of the virtual stop function of the interface management unit.

FIG. 14 is a functional diagram of the automatic meter reading data communication system.

FIG. 15A is a flowchart of a WAN processing portion of the data communication system shown in FIG.

FIG. 15B is a flowchart of a message sending part of the data communication system shown in FIG.

FIG. 15C is a flowchart of the RF processing part of the data communication system shown in FIG.

FIG. 15D is a flowchart of the scheduler portion of the data communication system shown in FIG.

FIG. 15E is a flowchart of a data storage portion of the data communication system shown in FIG.

Detailed Description of the Preferred Embodiment System As shown in FIGS. 5 and 6, the present invention provides an automatic meter reading data communication system 20 having an interface management unit 22 in communication with a gateway node 24. Here, the gateway node 24 is located remotely from the interface management unit 22. Between the interface management unit 22 and the gateway node 24,
There may be a relay node 26 shown in FIGS. 5B and 6B, which is located in the vicinity of the interface management unit 22 and provides additional communication power from the interface management unit 22 to the gateway node 24. The communication range of the interface management unit 22 is approximately 400 feet. Thus, if the gateway node 24 is more than 400 feet from the interface management unit 22, a relay node 26 is required to retransmit messages from the interface management unit 22 to the gateway node 24. The RF communication range between the relay node 26 and the gateway node 24 is about one mile.

The interface management unit 22 is a data collection device, which can be attached to the utility meter 28 of the residence, such as a water or gas meter, and collects data on the consumption of commodities such as water or gas consumption by the gateway node 24. Send to The interface management unit 22 may also be connected to other devices that monitor home security, environmental conditions, human health, the presence of smoke and carbon monoxide, and the like.

The gateway node 24 responds to the interface management unit 22 to obtain the data collected by the radio frequency (RF) communication link and sends the data to the utility service provider 30 via an installed wide area network (WAN) 34 I do.

In the preferred embodiment of the present invention shown in FIGS. 5A and 6A, a plurality of interface management units 22 attached to meters 28 of different commodities, such as water, gas and electricity, include a local area network (LA).
N) communicates with the gateway node 24 via 32, and the gateway node 24 transmits its commodity data from the interface management unit 22 to the utility 30 via the fixed carrier wide area network (WAN) 34. . Gateway node 24 provides end-to-end communication from meter 28 to utility 30. The first link in the data communication system is a two-way 900 MHz spread spectrum LAN 32.
The second link in the data communication system is designed with any commercially available two-way common carrier WAN. In the present embodiment, the gateway node 24 is the interface management unit 22
And within its communication range of approximately 400 feet. However, if the gateway node 24 is outside the communication range of the interface management unit, the relay node 26 prepares to retransmit data from the interface management unit 22 to the gateway node 24, as shown in FIGS. 5B and 6B. Can be The operating range of the relay node is approximately one mile. The relay node 26
The same RF transmission circuit as that of the interface management unit 22 and the gateway node 24 is used. Shown in FIG. 6B
LAN communication links 32A and 32B technically comprise the same links as LAN 32 shown in FIG. 6A. The only difference is that the gateway node 24 in FIG. 6B is outside the communication range of the interface management unit 22 and requires retransmission of data by the relay node 26.

The data collected from the interface management unit 22 is typically provided to a utility company computer and used to generate billing and commodity usage data.

Interface Management Unit Referring to FIG.
Is an integrated unit attached to the water, gas and electricity utility meter 28 by an adapter ring 36. The interface management unit 22 replaces the register head of the commodity meter using an adapter ring to retrofit the existing meter body with the interface management unit for meters manufactured by a wide range of manufacturers. This is accomplished by using programmable software in a plurality of different adapter rings 36 and interface management unit 22.

FIG. 3 shows the internal structure of the interface management unit 22. The interface management unit 22 includes an upper cover 40, a lower cover 46, and two printed circuit boards 42.
And 44. The printed circuit board 42 is preferably
RF antenna with cutout for liquid crystal display 38 on printed circuit board 44. LCD display 38
Displays meter readings, units of measure, tampers and status. The printed circuit board 44 includes various components and connectors as detailed in the block diagram of FIG. The interface management unit 22 is powered by a battery 50. Its compact integrated design and compatibility with various meters and meter brands show that it is a cost savings over the prior art.

The interface management unit 22 is an integrated digital encoder and two-way wireless transceiver,
Monitor the operation of utility meters 28, such as water, gas, and electricity meters, ascertain commodities usage by measuring pulses generated by rotors in the meters, and use commodities through RF local area networks (LANs). The quantity data is sent to the relay node 26 or the gateway node 24. The events measured by the interface management unit 22 are typically pulses generated by a turbine or other conversion element in response to flow to the commodity meter. Additional functions such as valve actuation output and modified input are also provided by the interface management unit
Provided for 22.

As described in detail below, the communication between the interface management unit 22 and the relay node 26 or the gateway node 24 transmits spread spectrum data having multiple channels in the adopted frequency band, preferably two-way 900 MHz direct spread. Established using technology. The interface management unit 22 performs an automatic meter reading function in response to a request from a utility, from a pre-programmed schedule read, or from a spontaneous alarm message. These automatic meter reading functions include monthly usage reading, remote first and last meter reading, real-time fraud detection and notification, virtual stop function, and alarm system function.
In addition, the interface management unit 22 attached to the water meter has the function of leak detection and low flow notification and works underwater in pit applications without a fixed antenna attachment. The interface management unit 22 attached to the gas meter can detect a runaway meter. Interface management unit 22 also performs security and information management tasks.

The interface management unit 22 is installed using a portable computer that programs utility identification numbers, meter settings and readings, units of measurement, and alarm set points. Once the interface management unit is installed,
It is connected to the gateway node via a two-way wireless LAN 32. As mentioned above, the interface management unit 22 does not need to be activated to send data. The interface management unit can initiate communication on its own, perform a pre-programmed scheduled read, or respond to requests from the utility via the gateway 24.

Communication Node The gateway node 24 is shown in FIG. Gateway node 24 is typically located on top of a utility pole to operate as a communication node between LAN 32 and WAN 34. It thus acts as a LAN to WAN connection.
Gateway node 24 includes an antenna 52 for transmitting and receiving data over the communication link, and a gateway node 24.
And a power line carrier connector 54 for connecting a power line for supplying power to the power line. Gateway 24 can also be powered by the sun. Due to its compact design, it can be easily installed on any existing utility pole or in similar high places. Gateway node 24 provides end-to-end communication from the meter to the utility. Wireless gateway node 24, 900MHz in two directions
It is connected to the interface management unit 22 via the spread spectrum LAN32. Also, the gateway node 24
To communicate with utilities, any WAN34
Connect with and fit. Gateway node 24 is field programmable to satisfy various data reporting requirements.

The gateway node 24 receives data requests for water, gas and electricity meter data and causes the meters to respond,
The usage data is transferred to the utility 30 via the WAN 34 together with the status data. It also provides a communication link to other secure security and information nodes. The gateway node 24 exchanges data with certain predefined interface management units for which it is responsible and "listens" for signals from those interface management units. Gateway node 24 does not store long-term data, thus minimizing security risks. The RF communication range of the gateway node is typically one mile.

The relay node 26 operates as an intermediate transmitting / receiving device that acquires an RF signal from the interface management unit 22 to the gateway node 24 and performs additional power enhancement. The relay node 26 is capable of both solar power supply and power supply via a power line carrier connection. Interface management unit 22 and gateway node 24
The same RF transceiver circuit found at
It is used for

A wide variety of stationary wide area network (WAN) communication systems such as those used for two-way pagers, cellular telephones, conventional telephones, personal communication services (PCS), cellular digital packet data (CDPD) systems, and satellite gateways It can be used to perform data communication between nodes and utilities. The data communication system utilizes channelized direct spread spread spectrum transmission for communication between the interface management unit, relay nodes and gateway nodes.

Interface Management Unit Circuit FIG. 7 is a block diagram of a half-duplex channelized direct sequence spread spectrum circuit board 44 in the interface management unit 22. The circuit board consists of four main functional components: a management microcontroller 56, a communication microcontroller 58, a spread spectrum processor 60, and a radio frequency (RF) transceiver 62.

The management microcontroller 56 performs the main interface function between the interface management unit 22 and the meter 28. This involves capturing and accumulating pulses from the utility meter converter 64. The entire accumulated pulse can be converted into a corresponding unit of commodity quantity and the result, which is displayed on a liquid crystal display (LCD) to visually indicate the commodity consumption. The administrative microcontroller also monitors inputs from unauthorized switches 66 for unauthorized use or status notifications. The microcontroller 56 is connected to a low battery detector 68 for monitoring battery power.

The microcontroller 56 also includes a data system management timer that controls power management functions. During normal operation, the managing microcontroller 56 is operating at a predetermined clock speed of, for example, 32.768 KHz, provided by an external crystal oscillator 70. All other elements in the interface management unit 22 are in a low power "sleep" mode or completely powered off. Periodically, a management microcontroller 56 applies power to other elements and
"Wake up" them to see if there are any RF signals to respond from. Typically, the application of power to activate may be every 2-8 seconds. If there is no signal to respond, power is removed from other factors or returns to a low power sleep mode. This technique is used to conserve battery power, thus extending battery life. If a valid response signal exists, the interface management unit 22 transmits the data to the relay node 26 or the gateway node 24.

The management microcontroller 56 may consist of a microprocessor component sold by Toshiba of Japan under the name TMP47P422VN.

The communication microprocessor 58 controls the radio frequency (RF) at the interface management unit 22, including determining whether the applied RF signal is a valid interrogation signal, and performing the actual data exchange with the gateway node 24. Responsible for all aspects of communications management. The microcontroller 58 uses a spread spectrum protocol and RF
Control information is provided to the spread spectrum processor 60 and the RF transceiver 62 to control channelization.

As mentioned above, when the communication microcontroller 58 is not communicating, it is in a "sleep" mode.

Communication microcontroller 58 is PIC16LC74-04 / L
And a microprocessor component sold by Microchip of Chandler, Arizona.

As described above, the data communication system 20 of the present invention includes:
Preferably, spread spectrum communication is employed between the interface management unit 22 and the gateway node 24 or the relay node 26.

Spread spectrum communication techniques typically use a signal structure such as sequential noise, such as a pseudo-noise (PN) code, to spread the narrowband information signal over a relatively wide band of frequencies. The receiver associates these signals and obtains the original information signal. This technology is a US patent
No. 5,166,952 and many of the references cited therein can be better understood.

As described below, using spread spectrum communication technology, when used with direct spread modulation technology, provides the data communication system 20 with security measures,
Increased resistance to interference, and 1 in a given environment
Provides the ability to operate one or more interface management units. The system operates over an extended range due to the improved signal-to-noise ratio. These communication technologies also
Eliminates the need to obtain rights from government agencies governing wireless communications.

The spread spectrum processor 60 functions to perform spread spectrum coding of data from the communication microcontroller 58 provided to the RF transceiver 62 and decoding of spread spectrum data from the RF transceiver. A spread spectrum processor is also provided for the communication microcontroller 58 and the frequency synthesizer 72 of the RF transceiver 62.
Generates a 4576 MHz clock signal. The spread spectrum processor 60 has the name SST32ADL, which includes a 9.8304 MHz crystal oscillator 74, data registers and encoding / decoding logic.
It may consist of an application specific integrated circuit (ASIC) gate array manufactured and sold by Cylink Corporation of Sunnyvale, California.

The encoding / decoding logic of the spread spectrum processor 60 samples the incoming serial data from the communications microcontroller and converts it to 32-bit pseudo noise (PN) at a rate divided by the crystal oscillator 74 by a factor of 192.
Convert to encoded data stream. Each set or "dibits" of serial data bits is represented by a unique 32-bit PN sequence.

FIG. 8 shows the RF receiver 62 of the interface management unit 22.
It is a block diagram of.

Communication to and from the interface management unit 22 may be performed in a pre-selected number of channels in a pre-selected band, e.g., 902 to 928 MHz, e.g., one of 24 channels. The interface management unit 22 receives data on the same one RF channel in this reception operation,
Send response. As described below, the specific RF channel used for communication depends on the unit configuration (commission).
ing) and selected during installation and loaded into memory. To avoid that two or more interface management units respond to the same interrogation signal, the RF channel is selected to be different from the operating channel of the other adjacent interface management unit.

The frequency synthesizer 72 modulates and demodulates the spread spectrum data supplied by the spread spectrum processor 60 into a carrier signal and demodulates the carrier signal into such data. The RF transceiver has a separate transmitter 76 and receiver 78 sections, which are fed by a frequency synthesizer 72 shared by the two sections.

The antenna 80 transmits via the band-pass filter 82-
Connected to the receive antenna switch 84 and operated by the communication microcontroller 58, the communication microcontroller 58 connects the desired one of the transmitter 76 or the receiver 78 to the antenna 80.

The output of the spread spectrum processor 60 to the frequency synthesizer 72 comprises a 2.4576 MHz reference frequency signal on lead 86 and a PN coded baseband signal on lead 88. Frequency synthesizer 72 is National Semiconductor's
It can be configured with an LMX2332A dual frequency synthesizer.

The direct spread modulation technique employed in frequency synthesizer 72 uses a high-speed binary code (PN code) to modulate the baseband signal. The resulting spread signal is used to modulate the transmitter's RF carrier signal.
The spreading code is a fixed length PN sequence of bits called chips, which is constantly recycled. The pseudo-random nature of the sequence allows for the desired signal spreading, and the fixed length sequence allows the code to be duplicated at the receiver for signal recovery. Therefore,
In direct spreading, the baseband signal is modulated by a PN code spreading function and the carrier is modulated to generate a wideband signal.

Minimum phase modulation (MSK) is used for reliable communication, efficient use of the radio spectrum, and low element count and low power consumption. The modulation performed by the frequency synthesizer 72 is a minimum phase modulation (MSK) with a chip rate of 819.2K chips per second, providing a 6dB instantaneous bandwidth of 670.5KHz.

The reception band of the interface management unit 22 is a minimum band of 900 KHz and usually 1 MHz. The frequency resolution of the synthesizer is 0.2048-MHz and is used to channel the band into 24 channels with a minimum of 1.024Mz spacing. This frequency channelization is used to provide future expansion, advanced features associated with this data communication system, and to minimize interference between interface management units within common communications.

The frequency control of the oscillator for RF in the system is
Double phase locked loop (PLL) in frequency synthesizer
Supplied by Its phase locked loop circuit (PLL)
Are controlled and programmed by the communication microcontroller 58 via the serial programming control bus 100 shown in FIG. As shown in FIG. 9, the frequency synthesizer 72 generates two RF signals, and the two RF signals are mixed in various combinations to generate a transmission carrier and demodulate the input RF signal. The transmitted carrier is supplied on conductor 102
Based on frequencies in the range of 82 to 807 MHz, the demodulated signal is
Based on a frequency in the range of 792 to 817 MHz provided at 4. These signals may be referred to as RF transmissions and RF signal local emission signals.

Table I below summarizes the transmission channel frequencies and the associated frequency synthesizer transmit / receive power on leads 102 and 104. The signals in the table are the two PLs in the dual frequency synthesizer 72.
Provided by L section.

The third signal, fixed at 120.4224 MHz, also
Supplied by a heavy frequency synthesizer. This signal is
6 and may be referred to as an intermediate frequency (IF) local emission signal.

RF transceiver 62, RF receiver section 78, low noise amplifier
108, the input of which is connected to the transmit-receive switch 84. The output of the low noise amplifier 108 is connected to an intermediate frequency (IF) signal mixer 110. Signal mixer 110
The other input to is the output from frequency synthesizer 72 on lead 104. The output of signal mixer 110 is an intermediate frequency signal sent to intermediate frequency signal mixer 114 via bandpass filter 112. Another input to the intermediate frequency signal mixer 114 is 120.422 from the frequency synthesizer 72 on line 106.
This is a fixed frequency signal of 4 MHz. Intermediate frequency signal mixer 11
4 converts the received signal to the final intermediate frequency, for example, 9.8304M
Convert to Hz.

The intermediate frequency signal from the intermediate frequency signal mixer 114 is
The signal passes through a band-pass limiting circuit including a band-pass filter 116, an amplifier 118, a band-pass filter 120, and an amplifier 122.

The signal from the amplifier 122 is supplied to a quadrature frequency discriminator 124 including a band-pass filter 126 and a signal mixer 128. The output of the frequency discriminator 124 is supplied to a linear phase low-pass filter 130 and a voltage comparator 132. The output of voltage comparator 132 on lead 134 comprises the received baseband data signal for interface management unit 22. The signal on lead 134 is provided to spread spectrum processor 60 and then to communication microcontroller 58.

In the transmission mode, frequency synthesizer 72 has a frequency in the range of 782 to 807 MHz on lead 102 and provides a modulated signal of the data to be transmitted. RF transmitter section 76 converts the signal on lead 102 to a fixed frequency on lead 106.
It has a signal mixer 136 for mixing with the IF local transmission signal. This results in RF signals in the range between 902 MHz and 928 MHz. The signal is filtered by a bandpass filter 138 to reduce harmonics and out-of-band signals, amplified by an intermediate power amplifier 138, and provided to a transmit / receive switch 84.

Operation of the Interface Management Unit The management of system timing and power within the interface management unit 22 is controlled by a management microcontroller 56. The communication hardware of the unit is periodically powered up from sleep mode to test for the presence of the interrogation signal from gateway node 24. 11A to 11C are flowcharts of power management and system communication of the interface management unit 22 according to the present invention.

Referring to FIGS. 7 and 11A-C, the episode of the request communication consists of three distinct stages. The wake-up interval of the communication hardware of the interface management unit, sometimes referred to as "blinking", the polling data from the gateway node, and the response from the interface management unit. The response may include a meter count indicating the amount of commodities consumed.

Due to the need to conserve battery power, the interface management unit is operated in a pulsed mode, which is woken up from sleep mode at regular intervals, typically 2 to 8 seconds. The interface management unit starts from a sleep mode, as indicated by reference numeral 300 in FIG. 11A.

Referring to FIGS. 11A-11C, the communication microcontroller 58 activates the RF receiver 78 periodically in short or “blink” intervals in response to a signal from the managing microcontroller 56. , Determine if there is a signal from gateway node 24 on the RF channel established for the interface management unit. See step 302. The signal from the gateway node 24 is composed of spread spectrum PN data that the interface management unit 22 can recognize as a valid interrogation signal. If there is no spread spectrum PN data or if the data there is invalid, the receiver 78
Stops and returns to “sleep”. If the PN sequence is found to be valid, receiver 78 remains on until the communication episode is completed.

Since the interface management unit 22 is not continuously monitoring the data, the gateway node 24 needs to “wake up” the interface management unit before sending data. Polling or configuration data
Only sent after enough time for the interface management unit to wake up. The interface management unit responds with the requested information immediately after the polling is completed. Once the communication episode has ended, the interface management unit resumes normal operation of blinking to test for a signal from the data interrogator on the RF channel.

In step 304, the spread spectrum processor 6
The management microcontroller 56 asserts low a power control line that powers 0 and starts all oscillators in the interface management unit 22,
The blinking cycle starts. In step 306, after a period of time after the oscillator has started and settled, the managing microcontroller supplies a pulse on the activation line 142 to activate the communication microcontroller 58. The communication microcontroller 58 generates an "active" signal on line 144 to the management microcontroller 56, indicating that the management microcontroller 56 is active and must keep the elements of the interface management unit operational. The management microcontroller 56
Shown in This is shown in step 308.

The next step in the communication process, step 31
0 is polling by the gateway node 24. In order for any meaningful data interchange to occur, the spread spectrum processor 60 must be loaded with PN codes and mode control data. In this code, every set of serial data bits, called "dibits", is represented by a unique 32-bit PN sequence. It is also necessary to load the appropriate channel programming data into the MSK frequency synthesizer 72 via the control bus 100. Spread spectrum data is transferred between the communication microcontroller 58 and the spread spectrum processor 60 via an 8-bit control bus 146.

After the frequency synthesizer 72 has been programmed to the correct RF channel, the RF channel is sampled to obtain valid spread spectrum data. See steps 312 and 314. Direct spread spectrum serial data is transmitted at a rate of 2400 bits per second in all communication episodes.

Once the RF transceiver 62 is stable, demodulated data is available at the input of the spread spectrum processor 60. Spread spectrum processor if a valid code is received
60 asserts a "lock detected" signal 148 to the communication microcontroller 58 in step 316. If the lock detect signal is not activated on lead 148 within a predetermined time, interface management unit 22 returns to sleep mode. However, if lock detection occurs, serial data will appear at the input of the communication microcontroller 58. See step 318. When the gateway node 24 finishes transmitting the packet data,
Stop the transmission on the RF channel and lose the lock detect signal after some random time of the end of the transmission. Once lock detection is lost, power to RF receiver 78 is removed. See step 320.

The serial data at the input to the communication microcontroller 58 is decoded by the communication microcontroller to determine the validity of the received message. If the message is correctly ordered and the serial number data contained in the message matches the serial number of the interface management unit that received the message, the data is transmitted via serial data leads 150, 152 and 154 to the communication microcontroller. 58 operates as a master and is interchanged with the management microcontroller 56. Message communication microcontroller 58
To the management microcontroller 56. When the management microcontroller 56 responds, the conductor 156
Activating the slave enable signal of the serial interface system reverses the direction of the master / slave relationship in the serial interface system. The data is then returned using the management microcontroller as the serial interface clock. The slave enable signal is removed when the message is completed. See steps 322, 324, 326 and 328.

This data exchange is performed for each received message except for the request for the valve operation message and the serial number message. If no data exchange is required, a response to the effect is sent.

After the request data (anything) is returned from the managing microcontroller 56 to the communication microcontroller 58, a return message to the gateway node 24 is formed at step 330. When the communication microcontroller 58 transmits, the communication microcontroller 58 must reprogram the frequency synthesizer 72 to change its frequency offset. This is done on the control bus 100. The RF transmitter 76 and the spread spectrum processor 60 are enabled to send a response by the interface management unit 22. After the elapse of the time when the spread spectrum processor 60 stabilizes, a return message is transmitted. This message is stopped by disabling the spread spectrum processor 60 and the RF transmitter 76. See steps 332-340.

Following completion of the transmission, at step 342, the RF receiver 7
8 is activated again to check for further input data. This is done because once the interface management unit 22 is awakened, multiple messages are exchanged without having to complete the activation cycle for each message. If the communication microcontroller 58 does not catch the input message within a predetermined time, the interface management unit returns to the sleep mode. See step 44. Frequency synthesizer 72
Is returned to the low power mode by a message on the control bus 100 and leads 14 to the management microcontroller 56.
The activity hold signal at 4 is sent to inform the management microcontroller that communication has ended. See step 346. The management microcontroller 56 then removes power to the rest of the interface management unit 22. See step 348.

Communication between the managing microcontroller 56 and the communication microcontroller 58 is achieved via a serial interface bus consisting of signals 150, 152 and 154.
All intra-processor communications consist of control code bytes, data bytes, and checksum bytes. A message requesting information consists of only control code bytes and checksum bytes. The checksum is a two's complement checksum.

 One example of a communication episode may be described as follows.

The RF receiver 78 of the interface management unit 22 is activated, and returns to sleep if no data is found. Then, RN
When the receiver starts up and finds the spread spectrum PN sequence from the gateway node 24, it recognizes it and waits for the generation of polling data from the spread spectrum processor 60. Once the unit has been activated, it receives and decodes the polling message from gateway node 24 and forms an appropriate response.

During the startup interval, the gateway node 24
The spread spectrum processor 60 sends a continuous idle state that synchronizes and confirms that the blinking window of the interface management unit is open long enough to find the incoming PN sequence. Once code lock is achieved, the monitoring interval is extended to accept input data. This is because the activation is considered successful if the code lock is achieved. If a code lock occurs, but the message is not acknowledged or no data is seen within a predetermined time window, the communication microcontroller 58 returns to sleep.

After unit 22 is successfully activated, gateway node 24 must command to perform one of a number of predetermined functions. If the unit responds to the message, it clears the most significant bit and returns a control word with the meter serial number as confirmation of the origin of the return message. This scheme ensures that the gateway node 24 does not respond to any return data that did not originate from the intended interface management unit 22.

Each data message starts with a predetermined control code following the required data and a checksum of all bytes up to the checksum byte. The checksum is calculated by taking the two's complement of the sum of all bytes preceding the checksum byte. This allows the checksum to be tested by adding all of the message bytes including the checksum and testing for a zero result. Data types used for data exchange include: That is, meter count, utility serial number, RF channel, unit of measurement, meter type, conversion factor, error code, actuator port, transmission count, company identifier, software version, and manufacturer serial number.

FIG. 10 is a block diagram of a gateway node circuit.
The RF transceiver section 156 of the gateway node 24 is the RF transceiver section of the interface management unit 22
Same as 62. Spread spectrum processor 158 is also identical to spread spectrum processor 60 in interface management unit 22, so that frequency synthesis, modulation, demodulation, and spread spectrum control in gateway node 24 are the same as in the interface management unit.

The communication and management microcontrollers 58 and 56 in the interface management unit 22 are replaced with the initialization microcontroller 160 and the WAN interface module 162, respectively. The WAN interface module 162 is a two-way pager, power line carrier (PL
C), may incorporate the electronics of satellite, cellular telephone, fiber optics, cellular digital packet data (CDPD) systems, personal communication services (PCS) or other fixed wide area network (WAN) systems. The structure of the WAN interface module 162 and the initialization microcontroller 160 can vary depending on the desired WAN interface. RF channel selection is achieved via an RF channel selection bus 164 that connects directly to the initialization microcontroller 160.

The initialization microcontroller 160 controls the programming of the spread spectrum processor 158, the RF transceiver 156
Channel Selection, Transmit / Receive Switching, and WAN Interface Module 1 in Frequency Synthesizer 166
Control all node functions, including acquisition failure at 62. When the power is turned on, the initialization microcontroller 16
0 programs the internal interface of the spread spectrum processor 158, reads the RF channel selection from the interface management unit 22, and configures the system for communication on the frequency corresponding to the channel selected by the interface management unit 22.

The selection of the RF channel used for transmission and reception is performed by the RF channel selection bus 1 to the initialization microcontroller 160.
Achieved through 64. Valid channel numbers are 0 to 23
In the range. The input is debounced by software to minimize the possibility of noise at the input to the initialization microcontroller 160, which causes erroneous channel switching. Channel selection data is
Before the initialization microcontroller accepts and initiates a channel change, it must be present and stable at the input to the initialization microcontroller 160 for approximately 250 μs. After a channel change is initiated,
It takes 600 μs for the frequency synthesizer 166 of the RF transceiver 156 to receive the programming data and for the frequency synthesizer oscillator to settle to its changed frequency. Channel selection may only be completed while gateway node 24 is in receive mode. If the RF channel selection line is changed during transmit mode, the change will not take effect until after the gateway node returns to receive mode.

Once the initial parameters have been established, the initialization microcontroller 160 initiates its monitoring function. When the gateway node 24 is in the receive mode, the initialization microcontroller 160 continuously
Monitor 64 to determine if a channel change has been implemented.

To receive the data, the gateway node 24 monitors the interface management unit 22 to determine if there is data. Some additional handshake hardware may be needed to recognize the presence of the spread spectrum signal.

The alarm message is automatically sent by the interface management unit 22 when the meter 28 is in a fraudulent or alarm state. The message is sent periodically until the error is cleared. Gateway node 24
Must know how many bytes of data you are looking at, and count them as they come in. Once the appropriate number of bytes have been received, the reception is complete and the message is processed. Any deviation from the expected number of bytes received may be a false message.

During the transmission mode of the gateway node 24, the initialization microcontroller 160 monitors the data lines to detect idle states, start and stop bits. This prevents the gateway node 24 from continuously transmitting meaningless information in the event of a failure of the WAN interface module 162, and prevents erroneous accompanying edge data that does not end transmission in a timely manner. This is done to prevent it from being sent. The initialization microcontroller 160 controls the RF transceiver 156 unless the data line is in an invalid idle state when communication is initiated.
Do not enable the RF transmitter 168.

The second watchdog function of the initialization microcontroller 160 when the gateway node 24 is in the transmit mode is to test for valid start and stop bits in the transmitted serial data stream. Thus, it can be confirmed that the data has been read correctly. The first start bit is defined as the first falling edge of serial data after entering the idle stage. All further timing during the communication episode is referenced from the start bit. The timing of the stop bit location is measured from the rising edge of the start bit for that particular data byte. The initialization microcontroller 160 measures a 9.5 bit time interval from the start bit edge and looks for a stop bit. Similarly, the one-bit interval timer starts at its 9.5 bit point to look for the next start bit. The next start bit is 9.5
If it does not activate itself within one bittime of the bittime maker, a failure is declared. The response to the failure state is to render the RF transmitter 168 inoperative.

Interface management unit settings (commissionin
g) If the interface management unit is first installed, it does not include utility serial number, meter scaling, or RF channel information. These constants must be programmed during installation and commissioning so that the interface management unit is compatible with the utility billing software and meter type. FIG. 12 shows a flow of starting the use of the interface management unit.

When the interface management unit is manufactured, by default the first RF channel of the internal frequency list is set. This known channel is used for speed generation line testing and interface management unit activation. When the interface management unit is installed, the setting device sends the utility serial number, meter scaling characteristics,
And program the RF channel selection data. Steps
See 360. And it first tries to get a response on the default RF channel. If there is no response from the default channel, the activation device moves to the next channel in the frequency list and repeats the process until the interface management unit responds. This allows the setting device to set a new meter and reset a meter already in use.

In order for the interface management unit to function as part of the network and coexist with other interface management units in the area, it may be necessary to adjust the operating frequency to minimize data collisions. This task must be done during the initial configuration of the interface management unit and is the responsibility of the configuration device. In a fixed local area network setup, all interface management units can occupy the same frequency, since they are accessed at once by serial number.

Each interface management unit has a finite distance, typically 400 feet, that can transmit and receive RF signals. In order for the gateway node to successfully communicate with the interface management unit, it must be within a finite distance where it can send and receive RF signals, otherwise it will install relay nodes to augment the RF signals It is necessary. As described above, since there is a unique serial number request as part of the polling procedure by the gateway, it is possible to have all interface management units on the same channel in the network setting. Even if multiple interface management units monitor the polling message, only the designated serialized unit will respond.

Assignment of interface management unit frequency
Performed by the configuration device during installation. This is achieved through the use of RF interrogation to determine the presence of interfering interface management units or other colliding RF signals. See step 362.

In step 364, at the start of the survey, the configuration device sends a serial number message on the first or default RF channel. Since this is a serial number independent message, the interface management unit within range of the initialization device must respond. If the configuration device does not get a response on this channel, it labels it as available and the probe stops. However, if a channel is being used, the configuration device moves to the next channel in the list, as shown in step 366. This process is
Repeat until an unused channel is found or all 24 channels have been examined. See step 368. Once an unused RF channel is found, the configuration device will display the utility serial number,
The operating RF channel and all remaining meter parameters are programmed into the memory of the interface management unit. See steps 370 and 372. The utility serial number, RF channel and other meter parameters can be changed at any time by a "serial number setting" message from the setting device, as shown in step 374.

The same RF frequency can be used many times. For example, if the installer moves out of range of the interface management unit on channel 1, this channel will also be usable by other interface management units.
This plan takes into account the actual radio propagation conditions in the area,
It is preferred for pre-assigned frequency planning because it does not require detailed pre-planning or complex diagrams of the channels.

Operation of Virtual Stop Function of Interface Management Unit FIG. 13 is a flowchart of the virtual stop function of the interface management unit of the present invention.

The virtual stop function of the interface management unit is used in situations where utility services are temporarily stopped, such as a change of owner. If the inhabitants are gone, there should be no noticeable consumption of utilities at that location. If there is any meter movement indicating leakage or misuse, the utility must be notified. This fraudulent mode condition provides a means of alerting and reporting of meter movement above a current threshold.

Activation of the virtual stop mode is achieved through a "set virtual threshold" message and is defined as a meter value that the interface management unit does not exceed. In order to know where to set the threshold, it is necessary to know the current meter value. The relay node, gateway node, configuration device, or other interface management unit communication device reads the meter values in steps 376 and 378, adds the appropriate offset in step 380, and enters the "virtual stop setting" in step 382. "The result must be sent to the interface management unit as a message. Then, in step 384, the interface management unit activates the virtual stop mode. In step 386, the interface management unit stores the meter value. If the meter value is greater than the current threshold, steps 388 and 390
"Error code clear" as detailed in
The interface management unit sends an "send alarm" message to the gateway node until the message is issued from the gateway node in response. However, if the meter value is not greater than the current threshold,
As shown in step 392, the interface management unit continues to monitor the meter value. Virtual stop mode is
In step 394, it can be cleared at any time by an "error code clear" message from the gateway node.

If the meter value in the interface management unit does not exceed the current threshold at a given sampling time, the unit will either (step 392) reach the current threshold or (step 394) until the virtual stop mode is released. Continue measuring.

Automatic Meter Read Data Communication System FIG. 14 is a functional flow diagram of the automatic meter read data communication system of the present invention, with elements shown as functional blocks. The flow diagram includes the main functional elements of the gateway node 24, including the message dispatcher 200, RF
It includes a processing unit 202, a WAN processing unit 204, a data storage element 206, and a scheduler element 208. The data storage and scheduler elements consist of data pre-programmed into the memory of the gateway node. The gateway node is connected to the interface management unit or the relay node 210 via a two-way wireless LAN. The gateway node 24 is also connected to a utility service provider via the fixed carrier WAN.

FIG. 15A is a detailed functional diagram of the WAN processing unit 204 in FIG. In a typical communication episode, utility 212
Initiates a request for data from the interface management unit 212 by transmitting a data stream over the WAN. WAN processing part of gateway node is WAN
It receives the data stream, creates a WAN message, identifies the sender's utility ID from data store 206, and sends the WAN message to message dispatcher 200 at the gateway node.

Here, referring to FIG. 15B, the message sending unit 200
Utility to receive WAN message from WAN processing unit
Determine the request from 212. The message sender 200 determines that the last recipient or target is the interface management unit or relay node 210. Then, the message transmission unit collates the interface management unit ID from the data storage unit 206, generates an RF message, and transmits the RF message to the RF processing unit 202.

Referring to FIG. 15C, the RF processing unit includes a message sending unit 200.
Receives RF messages from, selects the appropriate RF channel, converts the RF messages into RF data streams,
And sends the RF data stream to the interface management unit or the relay node 210 via a.
Then, the interface management unit responds by transmitting the RF data stream to the RF processing unit 202 of the gateway node 24 via the LAN. The RF processing unit 202 receives the RF data stream, generates an RF message from the RF data stream, and transmits the RF message to the message sending unit 200. As shown in FIG.15B, the message sending unit receives the RF message, determines a target utility for a response from the data storage unit 206,
N message is generated and the WAN message is sent to the WAN processing unit 2
Send to 04. The WAN processing unit 204 receives the WAN message from the message sending unit, converts the WAN message into a WAN data stream, and, as shown in FIG.
Send the data stream to the utility via the in-house telecommunications carrier WAN to complete the communication episode.

The communication episode is also initiated by a read according to a pre-programmed schedule in the scheduler 208 of the gateway node, as shown in FIG. 15D. The list of schedule read times is pre-programmed into memory in the gateway node 24. The scheduler 208 is executed periodically at the time of reading according to a schedule. When the schedule reading time comes, the scheduler 208 acquires information on the interface management unit or the relay node from the data storage unit 206, generates an RF message, transmits the RF message to the RF processing unit 202, and receives the RF message. , Select an appropriate RF channel, convert the RF message to an RF data stream, send the RF data stream to the interface management unit or relay node 210, and wait for a response. Then, the interface management unit responds to the RF processing unit 202 with the RF data stream. RF processing unit 202
The RF data stream is received, an RF message is generated from the RF data stream, and the RF message is transmitted to the message transmitting unit 202. The message sending unit receives the RF message, determines a target utility for a response from the data storage unit 206, generates a WAN message, and transmits the WAN message to the WAN processing unit 204. W
The AN processing unit receives the WAN message, converts it into a WAN data stream, and sends the WAN data stream to the utility 212.

In some cases, the utility may request data stored in the gateway node's memory. In this case, the utility starts a communication episode by sending the WAN data stream to the WAN processing unit 204. The WAN processing unit receives the WAN data stream, generates a WAN message, checks the utility ID of the sender in the data storage unit 206, and transmits the WAN message to the message sending unit 200. As shown in FIG. 15B, the message sending unit 200 receives the WAN message and
Determine the request from Then, the message sending unit 200
Determines the target of the message. If the requested data is stored in the gateway node's memory, the gateway node performs the requested task,
Determines that the requested utility is the target utility for the response, generates a WAN message,
The WAN message is transmitted to the WAN processing unit 204. The WAN processing unit 204 receives the WAN message, converts the WAN message into a WAN data stream, and sends the WAN data stream to the utility 212.

The last type of communication episode is one initiated by the interface management unit. in this case,
The interface management unit detects an alarm or an improper state and sends the RF data stream to the gateway node 24.
To the RF processing unit 202. The RF processing unit 202 receives the RF data stream, generates an RF message from the RF data stream, and transmits the RF message to the message sending unit 20.
Send to 0. Message sending section 200 receives the RF message, determines a target utility for a response from data storage section 206, generates a WAN message, and transmits the WAN message to WAN processing section 204. WAN
The processing unit receives the WAN message, converts it into a WAN data stream, and sends the WAN data stream to the utility.

Thus, there are three different types of communication episodes that can be implemented in the automated meter reading data communication system shown in FIGS. 14 and 15A-E.

FIG. 15D shows information or data pre-programmed in the gateway node memory. The memory contains a list of schedule read times performed by the interface management unit. These reading times can correspond to monthly or weekly usage readings and the like.

FIG. 15E shows data or information stored in the memory of the gateway node that handles the registered utility information and the registered interface management unit information. This data includes the utility identification number of the registered utility, the interface management unit identification number of the registered interface management unit, and other information for the particular utility and the particular interface management unit, and thus the gateway node Can communicate directly with the desired utility or the correct interface management unit.

It is recognized that other equivalents, alternatives and modifications other than those described above are possible within the scope of the appended claims.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Dressel Huiz, Don Earl 53211, Wisconsin, United States, 53211, Shorewood, North Lake Drive 3565 ) Surveyed field (Int.Cl. ⁷ , DB name) G08C 15/00-15/12

Claims (17)

(57) [Claims] 1. An automatic meter reading data communication system for acquiring commodity usage data from a commodity meter, comprising: an interface management unit attachable to the commodity meter;
A gateway node communicating with the interface management unit over a two-way wireless local area network, the interface management unit including a housing containing a digital encoder having an input for obtaining commodity usage data from a commodity meter. Further comprising: software programmable to interpret commodity usage data according to the type of commodity meter to which the interface management unit is attached; An automatic meter reading data communication system that communicates with utility service providers over the telecommunications carrier's wide area network. 2. The interface management unit obtains commodity usage data from the meter, stores the data, a digital encoder having an input connectable to the meter, and transmits commodity usage data from the meter. The data communication system according to claim 1, further comprising: a two-way wireless transceiver connected to the digital encoder for receiving a data request from the gateway node. 3. The gateway node transmits an interrogation signal to the interface management unit, receives a commodity use data from the interface management unit, receives a data request from the utility, and sends a commodity to the utility. A wide-area network processing unit for transmitting usage data; a message sending unit for transmitting and processing an interrogation signal and commodity usage data; a data storage memory for storing utility information and interface management unit information; The data communication system according to claim 1, further comprising a scheduler for storing a pre-programmed list. 4. The data communication system according to claim 1, wherein said two-way wireless local area network utilizes radio frequency spread spectrum communication technology. 5. The wide area network processing section,
5. The data communication system according to claim 4, wherein the data communication system utilizes a commercially available fixed telecommunications carrier wide area network system. 6. The data communication system according to claim 1, wherein said gateway node can start communication in said data communication system in response to a utility request message from said utility service provider. 7. The data communication system according to claim 3, wherein said gateway node is capable of starting communication in said data communication system in response to a read message of a pre-programmed schedule from said scheduler. 8. The data communication system according to claim 1, wherein said interface management unit is capable of starting communication in said data communication system in response to an alarm or an illegal state. 9. The data communication of claim 1, further comprising a relay node located between the interface management unit and the gateway node for retransmitting data and requests to and from the interface management unit. system. 10. The data communication system of claim 1, wherein said gateway node stores utility identification information, interface management unit identification, and scheduled meter reading in a memory. 11. A commodity meter having an interface management unit attachable to the commodity meter, and a gateway node remote from the interface management unit and communicating with the interface management unit over a two-way wireless local area network. An interface management unit for use in an automatic meter reading data communication system for obtaining commodity usage data from the gateway node, the interface management unit communicating with the gateway node and having an input connectable to the commodity meter. And a housing containing a digital encoder for acquiring commodity use data from the commodity meter and storing the data, and the interface management unit. Software programmable to interpret commodity usage data based on the type of commodity meter being used, connected to the digital encoder, transmitting commodity usage data from the commodity meter, and requesting data from the gateway node. Interface management unit having a two-way wireless transceiver. 12. The interface management unit according to claim 11, wherein the interface management unit is attached to the meter using an adapter ring. 13. The digital encoder includes a management microcontroller and a communication microcontroller connected to the management microcontroller, wherein the communication microcontroller controls internal and external communication functions of the interface management unit. A spread spectrum processor connected to the communication microcontroller, wherein the two-way wireless transceiver enables the interface management unit to transmit and receive data using spread spectrum communication technology;
Transmitting commodity usage data from the meter,
12. An RF transceiver connected to the spread spectrum processor receiving the interrogation signal from the gateway node and the communication microcontroller.
An interface management unit according to item 1. 14. The interface management unit,
The interface management unit according to claim 11, wherein the interface management unit is connected to a plurality of different meters and is programmable to respond to a need for reporting a plurality of different data. 15. A commodity meter having an interface management unit attachable to the commodity meter, and a gateway node remote from the interface management unit and communicating with the interface management unit over a two-way wireless local area network. An interface management unit for use in an automatic meter reading data communication system for obtaining commodity usage data from a communication device, wherein the interface management unit communicates with a remote gateway node to obtain and store commodity usage data from the meter. A management microcontroller having an input connectable to the meter, the remainder of the interface management unit for detecting an interrogation signal. A communication microcontroller connected to the management microcontroller, the communication microcontroller controlling internal and external communication functions of the interface management unit; and A spread spectrum processor connected to the communication microcontroller and enabling the interface management unit to transmit and receive data using spread spectrum communication technology; and a commodity used from the meter connected to the spread spectrum processor and the communication microcontroller. An interface management unit having an RF transceiver for transmitting data and receiving an interrogation signal from the gateway node. 16. A method for automatically reading data from one of a plurality of commodity meters and transmitting the data via a two-way wireless communication link, the method comprising: Selecting an adapter ring according to the type, attaching the adapter ring to the outside of the commodity meter, and attaching an interface management unit to the adapter ring attached to the commodity meter, the adapter ring comprising: Arranging the interface management unit so that the interface management unit can read the commodity usage data, the method further comprising: transmitting the commodity usage data via a two-way wireless RF spread spectrum local area network. Responding to the interface management unit using a gateway node remotely located from the interface management unit; and providing a signal to the gateway node via the local area network to provide the gateway node with an RF message, thereby causing the gateway node to respond. And transmitting the requested data from the gateway node to a utility service provider via an installed two-way telecommunications carrier wide area network. 17. The method of claim 16, further comprising the step of placing a relay node between the interface management unit and the gateway node for transferring signals between the interface management unit and the gateway node.