Consumption meter with error-correction

Description

Field of the Invention

[0001] The invention relates to an apparatus and system for transmitting messages relating to consumption data of factors provided. More particularly, the invention relates to a device and system for transmitting consumption data that can be received at different distances depending on the receiving device.

Background of the invention

[0002] Consumption meters for measuring consumption data of supplied media, for example electric meters, district heating heat meters and cold or hot water meters, are often equipped with a communication system for remote communication with the meter. Remote communication makes data collection much easier; there are different collection schemes for collecting data.

[0003] One type of collection scheme uses a portable collection system. In such a short-range system, data messages are broadcast from the meter, or from a communication device connected to the meter, to a collective system moving past the broadcast data collection device, typically either by passing the vehicle nearby or simply by passing nearby (collecting when passing or crossing). In such a system, it is possible to collect meter data without the need to enter the customer's premises - it is enough for a person or a vehicle to appear within the communication range of the transmitted signal. Portable collection systems can be simple and inexpensive.

[0004] In another type of collection scheme, stationary collection systems are used. In such a system, a communication network is built such that data is transmitted from the meter to a utility or other data reception station in a fully automatic manner. The advantage of such a system is that data can be received automatically and thus at constant short intervals if desired. However, the installation and maintenance of such a system makes it more expensive than a portable collection system, and often a large number of measurement sites are required in a given area to justify the costs.

[0005] In some cases, portable and fixed collection systems are combined into a so-called dual transmission system. In a dual transmission system, the transmitter transmits different data messages for reception by (at least) two different types of receiver devices. Dual teletransmission systems may be desirable, e.g., to provide a fallback data path to a data receiving station.

[0006] The prior art discloses a given number of dual transmission systems. US 7,626,511 discloses a dual teletransmission system in which the meter is adapted to transmit a plurality of narrowband signals at a limited power level and a plurality of wide spectrum signals with frequency hopping at a high power level. Narrowband signals are transmitted at intervals shorter than wide spectrum signals. In this solution, separate signals are used for different receiving devices.

Summary of the invention

[0007] It would be advantageous to have a teletransmission system that simply and flexibly supports portable collection schemes as well as permanent collection schemes for consumption meter data. In general, it would be advantageous to have a teletransmission system that simply supports a gathering scheme in which mixed transmissions that can be collected from different distances would provide a flexible pooling system. Generally, it may be seen as an object of the invention to provide a solution to the above-mentioned problems or other problems of the prior art.

In order to achieve such a solution, in a first aspect of the invention there is provided an apparatus for transmitting data messages relating to consumption data of the factors supplied, the apparatus adapted as a communication circuit of a consumption meter, the apparatus being adapted to encode and transmit a data message that comprises two parts:

the first part which contains the payload and is coded according to the communication protocol, and

a second part that includes error correction information to enable the receiving device to correct errors in the data message, characterized in that the data message is encoded such that the first part forms an independent data submessage which can be received independently of the second part by the receiving apparatus, wherein the data sub message is adapted to be received by the receiver within the first communication range, and the data message including the first and second parts is adapted to be received by the receiver in the second communication range, the second communication range being greater than the first communication range.

[0009] An apparatus is thus provided which supports that a consumption meter or communication device connected to the consumption meter can generate and transmit a single data message received at various distances from the meter by receiving devices of various types, depending on whether the receiver is adapted. to receive a data submessage or the entire data message. Thus, the first type of collecting device (e.g. Portable aggregate device) can be used to collect the meter data by receiving a data submessage, while a second type of aggregate device (e.g., a permanent collection device of a collective network) can be used to collect the meter data by receiving the entire data message. As an alternative to receiving the data submessage, a short-range receiver may be used, while a long-range receiver may be used to receive the entire data message. Usable content is of course an important part for the collection in order to obtain consumption data. The data sub-message can be collected within the communication range, and the user content can be received without error. By including error correction information in the data message, communication range can be increased at the expense of receiving a longer data message and either retransmitting a longer message or correcting the received data. Thus, the data sub message can be received as it is in the first communication range, while in the second, larger communication range, both the entire data message can be received due to error correction information and subsequent error correction.

[0010] The apparatus thus provides a single transmit circuit that can operate in a single transmission mode and yet transmit data messages supporting dual consumption data collection.

[0011] In a preferred embodiment, the error correction information is error correction information by applying turbo coding. The error correction information may thus be parity information generated by the turbo encoder, which may be used at the turbo decoder of the receiver to recover the data message. Another important error correction information is Low Density Parity Check (LDPC) codes. The turbo codes belong to the class of high performance correction coding (FEC) codes that allow communication close to the theoretical limit. LDPC codes can provide similar performance.

[0012] In a preferred embodiment, the apparatus is further arranged to transmit a further data message, the further data message being a data submessage. The data sub-message is shorter than the entire data message and requires less processing power to generate and receive it. The entire data message may be transmitted less frequently, and the data submessage, and thus the user content, more frequently. In this way, a long range data message can be provided simultaneously with a frequently broadcast short range message, e.g. for flexible data collection and low power consumption of the transmitter.

[0013] In a further aspect, the invention relates to a system for transmitting data messages relating to consumption data of the agents provided, the system comprising a data message transmitting device according to a first object, a first data receiving device and at least a second data receiving device. wherein the first data receiver is adapted to receive the data message and the second data receiver is adapted to receive the data message.

[0014] In a general embodiment, the first data receiver may be a short range receiver used to receive the data sub message and the second data receiver may be a long range receiver used to receive the entire data message.

[0015] Typically, the various features of the invention may be combined and coupled in any possible way within the scope of the invention. These and other aspects, features and / or advantages of the invention will become apparent and apparent from the embodiments described below.

Brief description of the drawing

Embodiments of the invention will now be described by way of example only with reference to the drawing, in which:

Fig. 1 shows schematically an embodiment of an AMR / AMI wireless network;

Fig. 2 shows a schematic overview of a general data message having two parts: a first payload part and a second error correction information part;

Fig. 3 schematically shows a transmitted data message signal;

Fig. 4 shows a transmitted signal that includes a data message and subsequent data messages; and

Fig. 5 schematically shows an encoder for encoding a data sub message and a decoder for decoding a received data message.

Description of the embodiments

[0017] In general, the data network for the remote reading of consumption meters can be built in several different ways based on different network structures. For an Automatic Meter Reading (AMR) or Advanced Measurement Infrastructure (AMI) network, the network should be robust, but also relatively cheap to build and maintain. AMR / AMI networks are often faced with challenges of high variability of the collection area in terms of meter density, meter placement, general radio conditions, i.e. presence of buildings, trees, vehicles, etc. Embodiments of the invention provide an AMR / AMI wireless radio network that supports flexible collection scheme.

[0018] Fig. 1 shows schematically an embodiment of an AMR / AMI wireless network according to the invention. The figure shows a meter 1, e.g. a water meter or heat meter, which measures the amount of supplied refrigerant used, e.g. the amount of water or heat consumed in a given household, and which provides meter data to the refrigerant owner for charging purposes. To collect consumption data from individual meters, the meters are arranged to transmit data messages 2 which include the data of the meter, so that consumption data can be remotely collected. For this purpose, the consumption meter is provided with communication circuits or circuits, or connected to circuits or communication circuits, which can transmit the collected consumption data on the data network.

In the embodiment shown, the data message 2 is received either by the portable collection device 3 or the fixed collection device 4, or both. The portable bulk device may be a handheld device, such as a specially programmed smartphone, or other electronic device. The portable collection device is shown as a car 3. Typically, the portable collection device is worn by the operator, either by passing the meter or by passing the meter (or a combination of both when measuring the collection route). The portable collection device can also be installed on a service vehicle such as a garbage truck. The fixed collection device 4 may be a concentrator or repeater for transmitting meter data to the factor provider 5 in an automatic manner. A fixed collective device is shown installed on an antenna mast, but it may be installed at other locations, but usually at a high location. It is shown that the fixed collective device is in direct contact with the factor 5 provider, e.g. by using GPRS, wireless internet, wired internet, etc. Typically, a more complex communication topology such as a multi-hop or multi-hop mesh topology can be used to transmit data from the collecting device to the factor provider.

[0020] The consumption meter 1 can be positioned at the installation site in several different ways. In one example, the meter is installed above the ground, such as in a shed or room in a house. In another example, the meter is installed underground in a sump. If the meter is installed in a pit, its meter communication system can be fully or partially mounted in the pit cover.

1 shows a portable collection device 3 and a fixed collection device 4. In exemplary embodiments, it is also possible to use two fixed collection devices. The first fixed manifold may be a short range fixed manifold and the second fixed manifold may be a long range fixed manifold. Such a system can be used to provide a backup reading in the event of a short-range power outage. In other embodiments, two portable collection devices may be used. A long-range data collection device is installed, for example, on a service vehicle for collecting data at predetermined periods. However, at other times, e.g., during holidays, service vehicle irregularities, or for other reasons, a portable collection device may be used to provide backup storage. In further embodiments, if desired, more than two types of collection device may be used.

The collecting system can support both one-way and two-way communication. In conjunction with unidirectional communication systems, mainly dual teletransmission systems are used. With corresponding receivers in the wear meter, embodiments of the invention can be made to support bi-directional communication.

[0023] Fig. 2 shows a schematic overview of a data message according to embodiments of the invention. The data message 2 includes two portions 20, 21. The first portion 20 includes a payload and the second portion 21 includes error correction information to enable the receiving device to correct errors in the data message either in the first message portion or in the entire message depending on the configuration. Typically, second portion 21 includes error correcting information to enable the receiving device to correct errors in at least the payload of the first portion of the data message.

[0024] The data message is coded such that the first portion 20 forms an independent data submessage that can be received by the receiving apparatus independent of the content of the second portion. The first part is coded according to a given communication protocol, such that any receiver device properly constructed to receive data messages according to this radio protocol can receive the data submessage 20 for further data processing, e.g., for receiving payload. The communication protocol may be, for example, the MBus protocol (EN 13757) or other suitable protocols for transmitting meter data. The communication protocol usually specifies the frequency range, communication channel, signal strength, etc. Data messages may be broadcast as radio signals, e.g. in the frequency range of 850 MHz to 950 MHz, such as the range of 868 to 870 MHz or in the range of 900 MHz to 915 MHz. Typically, however, any suitable signal frequency can be used.

[0025] Depending on the specific selection of signal parameters for the data message, the data sub message may be received with an allowable success rate in the first communication area 6. This first communication range depends on a number of factors and is different for obstruction free line of sight and communication. in a residential area with many obstructions.

[0026] The data message 2 further comprises a second portion 21 which together with the first portion 20 forms an extended data message. The second part includes error correction information which allows the receiver to receive the data message in the second communication range 7. By being able to correct for transmission errors, the second communication range is larger than the first communication range.

[0027] Fig. 3 shows schematically an embodiment of a transmitted signal in which the apparatus is arranged to repeatedly transmit a data message 2 at a first transmission frequency 30. The transmission frequency is shown as periodic. Periodic transmissions would be the normal situation in many cases, but usually a non-periodic transmission scheme can also be used.

[0028] Typically, in a portable collection scheme, the data message 2 must be sent frequently enough to be available to the collection device on aisle or drive-through at any collection time. In exemplary embodiments, the period may range from seconds to minutes. In a continuous collection scheme, the data message 2 may be sent less frequently, e.g. every hour, every few hours, once a day, once a week, or any other suitable frequency.

[0029] Typically the data message includes as part of the header a sync word to synchronize the transmission by indicating the end of header information and the start of data.

[0030] In an embodiment, a single (first) sync word 31 is used. First sync word 31 may be grouped with payload 32 of the data message. Thus, first sync word 31 and payload 32, possibly along with other data fields, may provide a consistent data message in the form of data sub message 20.

[0031] The first sync word may also typically be used to synchronize the receiver with the entire data message 2. However, it may be advantageous to include a second, stronger sync word 33 in the data message. In this way, the long range receiver can listen to the second sync word while the short range receiver listens to the first sync word. A stronger sync word may be needed to receive a data message at a greater distance than is possible with the first sync word which may be defined according to a given communication protocol.

[0032] The data message 2 shown in Fig. 3 further includes error correction information 34 and information block 35 used to transmit general information about the data message. The second portion 21 of the data message consists in this embodiment of data blocks 33, 34 and 35.

Thus, data message 2 comprises a data block constituting the second sync word 33, a data block constituting the first sync word 31, a data block constituting an information header 35, a payload data forming a payload 32, and a data block including error correction information 34. Generally in the message, consecutive and different data blocks may be used, and the order of the blocks may be different from that shown in Fig. 3.

[0034] Fig. 4 shows an embodiment in which the apparatus is further adapted to transmit a further data message, the next data message being a data submessage as such. In this embodiment, the data message 2 is transmitted repeatedly on the first transmission frequency 41 and the next data message 20 is transmitted repeatedly on the second transmission frequency 42. In an exemplary embodiment, either data message 2 or the subsequent data message 20 is transmitted at a given transmission frequency, with each nth consecutive data message being replaced by a data message 2 according to embodiments of the invention.

[0035] Such an embodiment may be used in a general gathering scheme where the short range sub message 20 is transmitted at a relatively high frequency to allow mobile data collection for traversal or near pass, and the data message 2 is transmitted as a long range transmission at a lower frequency. for a permanent collection device. Due to the relatively low long-range transmission rate of the data message, a longer battery life can be provided for both the battery-powered transmitter and the battery-powered long-range receiver of the data message.

[0036] In an embodiment, two data messages with different error correction information, albeit having a similar payload, may be transmitted repeatedly. In this embodiment, the first data message is structured such that a second part thereof includes the first error correction information and the second data message is structured such that the second part includes the second error correction information. The transmitting apparatus is adapted to repeatedly transmitting the first data message at the first transmission frequency and to repeating transmissions of the second data message at the second transmission frequency. In such an embodiment, the data signal can be adapted to two different types of long range receivers. Such signal may even further include a further data message in the form of a data submessage. Such a generic signal can be used in a very flexible collection scheme. An example of the use of such a signal is a system where a further data message is received by the home display device to provide the user with updated live consumption information, while the first data message is adapted to be collected portable by a service vehicle and the second data message is adapted to be collected by a service vehicle. backup network of fixed collective devices. In such an embodiment, the first data message may be constructed with less robust error correction information than the second data message, and thus require less energy to construct, transmit, and decode than does the second data message.

[0037] In various embodiments, the characteristics of the data message and the subsequent data message, ie, data submessage, may be diverse according to a given desired embodiment.

[0038] Depending on the desired embodiment, the data message and the subsequent data message are transmitted with the same signal strength or with a different signal strength. For example, it may be desirable to reduce the signal strength of the data message as compared to the subsequent data message to reduce transmission power consumption. The error correction capability can provide a sufficiently long transmission range with a lower transmit power compared to the subsequent data message.

[0039] In other examples, the data message and the subsequent data message are transmitted at the same center frequency or at different center frequencies, with the same signal bandwidth, or with different signal bandwidths, at the same data rate, or at different data rates. according to the desired transmission scheme.

[0040] In an embodiment, also the payload may be selected such that the data message and the subsequent data message are transmitted with the same payload or with different payloads. If the data message is executed as a fallback transmission, the payload can be customized to the desired backup information, while if short range collection is applied to at least part of the collection area and long range collection is applied to the rest of the collection area, it is usually desirable to use the same usable content in these two messages.

[0041] In an important embodiment, the data message is implemented as a system code. The systematic code allows the input data to be a direct part of an encoded error correction message. To obtain a systemically encoded message, turbo encoding or low-density parity-check (LDPC) encoding may be used to generate a data message that supports error correction according to embodiments of the invention.

[0042] For systematic codes, error correction information may be appended to the source block, such that the sub data message may be obtained separately from the entire data message with the error correction information.

[0043] In an embodiment, the receiver does not need to recover the original data submessage if it was correctly received. To achieve this, the data message further comprises a hash function such as a cyclic redundant checksum (CRC) to determine the correctness of the received data submessage.

[0044] Fig. 5 is a schematic illustration of an encoder 50 for encoding a sub data message and a decoder 51 for decoding a received data message to obtain an error correction data message. The encoder 50 may be implemented by the consumption meter communication circuitry, e.g., by the general consumption meter communications circuitry, or by the communications circuitry connected to the consumption meter to provide the consumption meter with a communication function.

[0045] In an embodiment, the sub-data message for user reporting to the owner of the consumption factor is generated by the consumption meter computing system. The data submessage or parts of the data submessage are fed to the encoder as input, dk. The encoder may be executed by the general computational circuitry in any suitable way supported by a given consumption meter.

[0046] In the shown embodiment of the turbo encoder, an encoder with a factor of 1/3 is shown. Three subblocks of bits are constructed. The first subblock is a data block in the form of an input xk data message. The second subblock is n / 2 parity bits, yki, for the input data computed using the recursive systematic convolutional code (RSC) by the Ci computator. The third subblock is n / 2 parity bits, yk2, for a known permutation of the input data also computed using the RSC code by the C2 computation system. Thus, two redundant but different sub-block parity bits are sent with the input data. Payload data permutation is performed by using an interleaver (IL) and a delay line (DL).

[0047] The turbo code encoder consists of two identical RSC encoders Ci and C2, each of which outputs a series of parity bits (yk1 and yk2), which in turn are arranged in relation to each other in a parallel concatenation scheme by a so-called punch puncturer P) to generate a combined block of parity bits, yk, to form error correction information. The punch operation is a systematic way to discard a portion of the input parity bits yk1 and yk2 to obtain the output throughput from P less than the total input throughput. The input data xk and error correction information yk are input to the consumption meter computation circuit T to be organized according to the format or protocol used for the data message, and transmitted as signal S constituting the data message.

[0048] The transmitted signal S with the data message is received as a signal received S 'by the receiver R of the collecting device.

[0049] The collecting device comprises or is coupled to a decoder 51 for decoding a received data message. A decoder usually requires slightly more computing power than an encoder, since decoding, i.e. reconstructing a received signal, is usually a computationally more demanding task than encoding the signal.

[0050] The received signal is split into input data x'k and parity data y'k. The parity data is input into a so-called DP depuncture to obtain two series of parity bits y'k and y'k2. The adder works with the opposite strategy to the punch, so that in cases where the punch has missed a parity bit, the adder inserts a special unknown parity bit so that the turbo decoder, TD, takes into account that the parity bit has never been sent in S. Three data blocks are input into a turbo decoder (TD) to compute the best input data estimate d_k.

[0051] Fig. 5 shows the turbo encoder 50 and the turbo decoder 51 in an overall form that may be used in conjunction with an embodiment of the invention. There are many different examples of turbo codes using different component encoders / decoders, input / output bandwidths, interleavers, and "punch" patterns. A person skilled in communication signal engineering is able to design a suitable encoding / decoding scheme.

[0052] Returning to Fig. 1, the figure shows an exemplary embodiment of a communication system for data messages regarding consumption of factors provided. The system comprises a transmitting device in the form of a consumption meter 1, a first data receiver in the form of a portable collection device 3 and a second data receiver in the form of a fixed collection device 4. In the overall system, a given number of consumption meters are disposed over a given area, a single portable collection device can be used and moved along the collection route, and a given number of fixed collection devices can be strategically placed to receive redundant transmissions from all meters in the collection area.

The consumption meters may transmit data messages as shown in Fig. 3 where only one type of data messages is transmitted, such as the data messages shown in Fig. 4, with two types of data messages being transmitted as well as more complex data signals. with a given number of different types of data messages. The system has been discussed with signals as shown in Figures 3 and 4, but one skilled in the art is able to extend the system to include other types of signals within the scope of the invention.

[0054] In conjunction with a signal of the type shown in Fig. 3, the first receiver 3 may be a handheld collective device, possibly a specially programmed smartphone that can receive data messages encoded according to the MBus wireless communication protocol.

[0055] The first receiver can listen for a sync word specified by the communication protocol and upon receiving such a sync word it will receive the wireless MBus part of the data message, i.e. the first part of the transmitted data message. Such data aggregation devices are known in the art. The second part of the data message will not affect the bulk portable device.

[0056] The second receiver 4 is located at a distance exceeding the expected communication range of messages transmitted via the wireless MBus protocol and even if it is able to detect the first sync word, the signal will usually be too noisy to be properly received.

[0057] In an embodiment, the second receiver listens to the second stronger sync word and receives the entire data message at the time of receipt of such sync word. Then either the entire data message will be sent to the factor provider, or the first portion of the signal will be played back by the second aggregate and this reconstructed first portion will be sent to the factor provider.

[0058] In an embodiment where the signal transmitted by the wear meter is as shown in Fig. 4, the system will operate in a practically similar manner as far as data collection is concerned. The portable bulk device will not know the difference between the entire data message 2 and subsequent data messages in the form of the first portion 20 of the entire data message. The portable batch device will simply see a periodic repeating MBus data message of the same type.

[0059] On the other hand, the fixed collective device will not see the next data message 20, but only the entire data messages 2 to be received as periodic repeating data messages.

[0060] While the invention has been described in connection with specific embodiments, it is not to be construed as limited in any way to the examples shown. The invention can be practiced by any suitable means; and the scope of the invention is to be interpreted in light of the appended set of claims. Possible reference numbers in the claims should not be construed as limiting the scope.