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Performance Evaluation of Power-Line Communication Systems for LIN-Bus Based Data Transmission

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Performance Evaluation of Power-Line Communication Systems for LIN-Bus Based Data Transmission electronics Article Performance Evaluation of Power-Line Communication Systems for LIN-Bus Based Data Transmission Martin Brandl * and Karlheinz Kellner Department of Integrated Sensor Systems, Danube University, 3500 Krems, Austria; [email protected] * Correspondence: [email protected]; Tel.: +43-2732-893-2790 Abstract: Powerline communication (PLC) is a versatile method that uses existing infrastructure such as power cables for data transmission. This makes PLC an alternative and cost-effective technology for the transmission of sensor and actuator data by making dual use of the power line and avoiding the need for other communication solutions; such as wireless radio frequency communication. A PLC modem using DSSS (direct sequence spread spectrum) for reliable LIN-bus based data transmission has been developed for automotive applications. Due to the almost complete system implementation in a low power microcontroller; the component cost could be radically reduced which is a necessary requirement for automotive applications. For performance evaluation the DSSS modem was compared to two commercial PLC systems. The DSSS and one of the commercial PLC systems were designed as a direct conversion receiver; the other commercial module uses a superheterodyne architecture. The performance of the systems was tested under the influence of narrowband interference and additive Gaussian noise added to the transmission channel. It was found that the performance of the DSSS modem against singleton interference is better than that of commercial PLC transceivers by at least the processing gain. The performance of the DSSS modem was at least 6 dB better than the other modules tested under the influence of the additive white Gaussian noise on the transmission channel at data rates of 19.2 kB/s. Citation: Brandl, M.; Kellner, K. Keywords: power line communication; local interconnect network (LIN); direct sequence spread Performance Evaluation of spectrum; automotive sensor network Power-Line Communication Systems for LIN-Bus Based Data Transmission. Electronics 2021, 10, 85. https://doi. org/10.3390/electronics10010085 1. Introduction Power line communication (PLC) is a versatile method using existing infrastructure Received: 30 November 2020 like power cables for data transmission. This makes PLC an alternative and cost-efficient Accepted: 28 December 2020 technology by the dual use of the powerline to other communication solutions like wire- Published: 4 January 2021 less radio frequency communication. The PLC modems can be installed plug and play on the existing power infrastructure without the need for other costly installation proce- Publisher’s Note: MDPI stays neu- dures. Typically the rooms on each floor and beyond are linked by the same power line tral with regard to jurisdictional clai- infrastructure which can be used easily for PLC. However, the PLC transmission channel ms in published maps and institutio- nal affiliations. is a very rough environment and need special attention to the design of the PLC [1–3]. PLC technology is a good alternative to wireless communication and is intended for use such as home automation, smart grid, city automation and cyber-physical systems as well as long-range communication. Another approaching field for PLC systems is given by Copyright: © 2021 by the authors. Li- the application in vehicular-, ship-, and aircraft- technology [4–14]. censee MDPI, Basel, Switzerland. Especially in vehicular technology CAN (Controller Area Network, ISO 11898) and LIN This article is an open access article (Local Interconnect Network, ISO 17987 [15,16]) buses are used for communication links distributed under the terms and con- between different components. The CAN bus offers data rates up to 1 Mbit/s (high speed ditions of the Creative Commons At- CAN) and the hard wiring between the CAN transceivers allows a lossless bitwise arbitra- tribution (CC BY) license (https:// tion method which makes CAN suitable as a real-time prioritized communication system. creativecommons.org/licenses/by/ This procedure also provides a hierarchy of messages among each other. The message with 4.0/). Electronics 2021, 10, 85. https://doi.org/10.3390/electronics10010085 https://www.mdpi.com/journal/electronics Electronics 2021, 10, x FOR PEER REVIEW 2 of 18 arbitration method which makes CAN suitable as a real‐time prioritized communication system. This procedure also provides a hierarchy of messages among each other. The Electronics 2021, 10, 85 2 of 18 message with the lowest identifier may always be transmitted. For the transmission of time‐critical messages, a high‐priority identifier can be assigned in order to give the messagethe lowest priority identifier during may transmission. always be transmitted. In vehicular For technology the transmission LIN buses of time-critical are typical used mes- forsages, low a‐speed high-priority and low identifier priority can communication be assigned in between order to givesub‐systems. the message For priority cost‐sensitive during andtransmission. low speed In applications vehicular technology mainly the LIN LIN buses bus are is used typical in used automotive for low-speed applications. and low The pri- LINority bus communication serves as a sub between‐bus for sub-systems. cost‐effective For networking cost-sensitive of control and low devices speed in applications cars. LIN is usedmainly for the simple LIN sensor bus is usedand actuator in automotive applications applications. where the The CAN LIN busbus serves was not as an a sub-bus option forfor this cost-effective cost‐sensitive networking area, as ofthe control bandwidth devices and in versatility cars. LIN are is used not required for simple and sensor the costsand actuatorfor networking applications with wherethis bus the are CAN too bushigh. was Up not to an16 optionbus subscribers for this cost-sensitive can be net‐ workedarea, as in the a bandwidthLIN cluster, and with versatility a maximum are notdata required rate of 20 and kbit/s. the costs The forLIN networking bus is typically with usedthis busfor non are‐ toocritical high. safety Up to components 16 bus subscribers and sensors/actuators can be networked in cars in where a LIN cluster,the applica with‐ tiona maximum area includes data comfort rate of 20 functions, kbit/s. The such LIN as window bus is typically regulators, used central for non-critical locking, electric safety mirrorcomponents adjustment, and sensors/actuators electric seat adjustment, in cars whererain sensor, the application light sensor, area electric includes sunroof, comfort or airfunctions, conditioning such ascontrol window etc. regulators, central locking, electric mirror adjustment, electric seat adjustment, rain sensor, light sensor, electric sunroof, or air conditioning control etc. The LIN‐Bus The LIN-Bus With the demand for a cost‐effective communication system for use in the sen‐ sor/actuatorWith the area, demand LIN found for a cost-effectiveits way into communicationthe vehicle as a system so‐called for “sub use‐ inbus”. the LIN sen- communicationsor/actuator area, was LIN very found simple its and way does into not the require vehicle a as communication a so-called “sub-bus”. controller LIN or crystalcommunication oscillator wasfor synchronization. very simple and doesThe data not require transmission a communication takes place controller via a single or crys-line (singletal oscillator wire). for In synchronization.order to meet the The interference data transmission immunity takes requirements place via a typical single line for (singlemotor vehicles,wire). In the order transmission to meet the interferencelevels correspond immunity to the requirements battery voltage typical but for with motor slew vehicles, rates µ belowthe transmission 2 V/μs therefore levels correspond limiting the to thesymbol battery transmission voltage but withrate slewto 20 rates kbit/s. below The 2 V/mas‐s tertherefore‐slave architecture limiting the symbolmakes LIN transmission communication rate to 20 deterministic. kbit/s. The master-slave A master controls architecture the entiremakes communication LIN communication in a LIN deterministic. cluster on the A masterbasis of controls a well‐defined the entire time communication table (Figure 1). in Onea LIN LIN cluster frame on consists the basis of of the a well-defined two parts header time table and response. (Figure1). The One header LIN frame is always consists sent of the two parts header and response. The header is always sent by the LIN master, while by the LIN master, while the response is sent by either one dedicated LIN slave or the the response is sent by either one dedicated LIN slave or the LIN master itself. A LIN LIN master itself. A LIN slave addressed by the message responds with a frame which slave addressed by the message responds with a frame which can consist of up to eight can consist of up to eight data bytes. Due to the six‐bit wide identifier up to 64 LIN mes‐ data bytes. Due to the six-bit wide identifier up to 64 LIN messages can be specified. sages can be specified. In contrast to CAN, LIN is a centrally controlled message distri‐ In contrast to CAN, LIN is a centrally controlled message distribution system. A LIN bution system. A LIN message always begins with the so‐called “break‐field”. This helps message always begins with the so-called “break-field”. This helps all LIN slaves to syn- all LIN slaves to synchronize and is used to activate all attached LIN slaves to listen to the chronize and is used to activate all attached LIN slaves to listen to the following parts of following parts of the header. The “break‐field” command consists of one start bit and the header. The “break-field” command consists of one start bit and several dominant several dominant bits with a length of at least 11‐bit times. Data integrity is checked using bits with a length of at least 11-bit times. Data integrity is checked using parity bits in parity bits in the message header and a checksum transmitted in the message response.
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