Proceedings of the IEEE SoutheastCon 2015, April 9 - 12, 2015 - Fort Lauderdale, Florida
A Time and Energy Efficient Parking System Using ZigBee Communication Protocol Abu Asaduzzaman and Kishore K. Chidella EECS Department
Wichita State University Wichita, Kansas, USA
[email protected]
major problem in large and busy traffic areas is Abstract—A parking vehicles by searching for empty (and available) spaces. In the recent days, some parking lot systems are equipped with sensors and microcontrollers to automatically count the cars parked in the lot. However, such a parking system may not any empty spots. In addition, existing systems are very indicate expensive and suffer due to long processing time and large energy consumption. Recently introduced ZigBee technology is a low-cost and low-power wireless communication protocol targeted towards automation and remote control applications. work, we propose a smart parking system for heavy In this traffic environments using ZigBee wireless transmission module. The proposed system is suitable for multi-floor buildings and able to send a message to vehicles about the status of parking spaces. The parking monitoring system continuously collects the data from parking slot detectors and then it intimates the vehicle section. We simulate the proposed system using ZigBee and two other popular wireless technologies: Bluetooth and WiFi. Experimental results show that ZigBee provides transition time and power advantages over Bluetooth and Wi-Fi.
Index Terms—ARM controller, infrared sensors, radio frequency, smart parking, ZigBee
I. INTRODUCTION With the fast development of economy, the demand for electricity is growing. The problem due to the gap of construction of network and inadequacy of transmission capacity becomes increasingly prominent [1]. A wireless personal area network (WPAN) is meant to span a small area such as a private home or an individual workspace. It is used to communicate over a relatively short distance. The specification does not preclude longer ranges being achieved with the trade-off of a lower data rate [2]. Some of the protocols employing WPAN include Bluetooth, ZigBee, Ultra-wideband (UWB), and Infrared Data Association (IrDA). Each of these is optimized for particular applications or domains. It has the ability to communicate at low power; with a data rate up to 250 kb/s. ZigBee is popular as it is easy for device co-ordination and interoperability with other wireless products. Typical ZigBee application domains include: agricultural, building & industrial automation, home medical monitoring, embedded sensing, security, control, toys, toys, and more toys [2]. The main advantage of using is the low current consumption and the ability of long ZigBee range communication, if the application is having good lineof-sight (LOS). Thus the solution for parking problem, which includes the fuel consumption and thus pollution, can be minimized by implementing the system with ZigBee. In this work, we implement the system using ZigBee, radio frequency (RF)IEEE communication, infrared (IR) sensors, and 00-5/15/$31.00 ©2015
978-1-4673-7300-5/15/$31.00 ©2015 IEEE
978-1-4673-7300-5/15/$31.00 ©2015 IEEE
Muhammad F. Mridha CSE Department University of Asia Pacific Dhanmondi, Dhaka, Bangladesh
[email protected]
advanced RISC (reduced instruction set computer) machine (ARM) microcontrollers. This technique improves the speed and reduces power consumption, which in turn makes the system less maintenance. This system is used to check the parking availability in multi-floors using RF and the decision can be made by ARM microcontrollers. The status can be sent to the vehicle by using ZigBee [3]. Thus a cost effective solution can be provided for the parking problems with less time and also saves fuel consumption. The proposed parking inquiry module is installed in vehicle for the existing cars or it can be integrated in the new cars that may further reduce the cost of the system. The parking monitoring system and parking slot detector is installed at parking site that may be in any multi-floor building. This paper is organized as follows: Section II presents some important concepts related to wireless communication. The proposed system is introduced in Section III. In Section IV, the proposed system is evaluated. Section V discusses some related published articles. Finally, this work is concluded in Section VI. II. SOME IMPORTANT COMPONENTS Some important components, helpful to understand the proposed system, are briefly discussed in this section. A. ARM Microcontroller ARM is a 32-bit architecture and can be implemented with two instruction sets like 32-bit instruction set or 16-bit thumb instruction set. The thumb instruction set is widely used to optimize the code density from C code, which is approximately 65%. It is the subset of the functionality of the ARM instruction set with improved performance. These instructions are produced from ARM C compiler from real application code and then these subsets of instructions compressed into 16-bit opcodes from narrow memory with better performance. It has 37 registers all of which are 32 bits long and are used for program counter, program status registers and general purpose registers. ARM9 micro controller due to its high-performance and low-power consumption gained their interest in processor field. ARM is one of the most licensed and thus widespread processor cores in the world. These are used especially in portable devices due to low-power consumption and reasonable performance [4]. It is a Von Neumann machine with load/store architecture and it contains 32-bit data bus for both instruction and data. Data types can be 16-bit half-words or 32-bit words. The interrupts are serviced based on the priority. Software Interrupt (SWI) handler can decide the type of operation requested by examining the SWI number. We can implement
Proceedings of the IEEE SoutheastCon 2015, April 9 - 12, 2015 - Fort Lauderdale, Florida
a set of privileged operations with the use of SWI mechanism when running in user mode. ARM7 and ARM9 have V3 and V4T architectures, respectively. It is designed with 5-stage architecture with fetch, decode, execute, buffer/data, pipeline and write back. The pipelining architecture reduces the time of execution and thus these are suitable for more real time applications. Sometimes the instructions cannot be executed in the stream due to hazards and these reduce the performance or the speed of the execution. There are 3 types of hazards: structural, data, and control.
to provide the upper layers of the protocol stack (from network to the application layer) for interoperable data networking, security services and a range of wireless home and building control solutions, provide interoperability compliance testing, marketing of the standard, and advanced engineering for the evolution of the standard. This will assure consumers to buy products from different manufacturers with confidence that the products will work together. Table 1 shows the advantages and limitations of ZigBee over other wireless networks [2].
B. Infrared Sensors Infrared sensors are used to know the vehicle parking slot availability. These are mostly used for remote control detection. Many electronic systems require control systems and feedback for many applications. These are generally tuned to listen to the infrared light. The objects above absolute zero temperature emit heat energy in the form of radiation and these can be detected by electronic devices, which are invisible to the human eye. The sensors generate energy when exposed to heat. The sensor detects the change in the infrared radiation and if it is higher than a predefined value then it gives the free slot information to the ARM microcontroller. The IR sensor generates a pulse of infrared light and is emitted from the emitter and spreads out. If the object is detected then the IR light will be reflected and some of it will hit the detector and thus knows whether the free space available for car parking.
TABLE I ZIGBEE, BLUETOOTH, AND WI-FI PARAMETERS
C. ZigBee Technology Bluetooth supports a very short range and relatively low bandwidth and these are mostly designed for handheld But due to the limitations in range and speed these devices. are very less considered in general purpose wireless localarea network (WLAN) networking applications. Wi-Fi supports Ad-Hoc mode and can be used as a public hotspot. But 802.11a standard does not support cross compatibility with any other. The speed varies with distance and the speed is reduced when the access point is at longer distance. The main focus in this paper is to find a parking-slot with low power consumption. ZigBee technology is a low power, low data-rate, low cost; wireless networking protocol targeted towards automation and remote control applications. IEEE 802.15.4 committee started working on a low data rate standard a short while later. Then the ZigBee Alliance and the IEEE decided to join forces and ZigBee is the commercial name for this technology. ZigBee is expected to provide low cost and low power connectivity for equipment that needs battery life as long as several months to several years but does not require data transfer rates as high as those enabled by Bluetooth. In addition, ZigBee can be implemented in mesh networks larger than is possible with Bluetooth. ZigBee compliant wireless devices are expected to transmit 10-100 meters, depending on the RF environment and the power output consumption required for a given application, and will operate in the RF worldwide (2.4GHz global, 915MHz America, or 868 MHz Europe). The data rate is 250kbps at 2.4GHz; 40kbps at 915MHz and 20kbps at 868MHz. IEEE and ZigBee Alliance have been working closely to specify the entire protocol stack. IEEE 802.15.4 focuses on the specification of the lower two layers of the protocol (physical and data link layer). On the other hand, ZigBee Alliance aims
00-5/15/$31.00978-1-4673-7300-5/15/$31.00 ©2015 IEEE ©2015 IEEE
Wireless Parameter Frequency band Physical/MAC layers Range
Bluetooth
Wi-Fi
ZigBee
2.4 GHz IEEE 802.15.1
2.4 GHz IEEE 802.11b
2.4 GHz
9m
75 to 90 m
IEEE 802.15.4 Indoors - 30m Outdoors (LOS) up to 100m
Current Consumption
60 mA (Tx mode)
Raw data rate Protocol stack size Typical network Join time
1 Mbps
400 mA (Tx mode) 20 mA (Standby mode) 11 Mbps
250 KB
1 MB
32 KB 30 ms typically
25-35 mA (Tx mode) 3 μA (Standby mode) 250 kbps
Interference avoidance method
FHSS (Frequencyhopping spread spectrum)
Variable, 1 sec typically DSSS (Directsequence Spread spectrum)
Minimum Bandwidth required
15 MHz (Dynamic)
22 MHz (Static)
3 MHz (Static)
Maximum nodes
7
32 per access point
64K
Number of channels
19
13
16
>3 sec
DSSS (Directsequence Spread spectrum)
IEEE 802.15.4 is now detailing the specification of PHY and MAC by offering building blocks for different types of networking known as “star, mesh, and cluster tree”. Network routing schemes are designed to ensure power conservation, and low latency through guaranteed time slots. A unique feature of ZigBee network layer is communication redundancy eliminating “single point of failure” in mesh networks. Key features of PHY include energy and link quality detection, clear channel assessment for improved coexistence with other wireless networks [5]. D. Radio Frequency Signals Radio frequency communication signals are engineered to trade off efficient use of the electromagnetic (EM) spectrum with the complexity and performance of the RF hardware required to process them. The process of converting baseband (or low-frequency) information to RF is called modulation of which there are two types: analog and digital modulation. In analog modulation, the RF signal has a continuous range of values; in digital modulation, the output has a number of
Proceedings of the IEEE SoutheastCon 2015, April 9 - 12, 2015 - Fort Lauderdale, Florida
prescribed discrete states. There are just a few modulation schemes that achieve the optimum trade-offs of spectral efficiency and ease of use with hardware complexity [6].
III. PROPOSED SYSTEM The smart vehicle parking is a tremendous technology in automobile field. Our proposed system is a smart vehicle parking using ZigBee module. Figures 1, 2, and 3 illustrate the proposed smart vehicle parking system. RF communication is used to get the status of parking available slots between the floors. The proposed system contains three modules: Parking inquiry module, parking monitor system, and parking slot detector. Parking inquiry module is installed or integrated in a vehicle. The parking monitor system is on first floor and parking slot detector is on second installed floor.
sends a message to the vehicle section regarding the space. This message is received by parking inquiry module in vehicle through ZigBee and displayed on the LCD. The information of parking request from vehicle section and the information status of parking slot available in second floor from parking slot detector is displayed on LCD, which is available in parking monitor system.
A. Parking Inquiry module The parking inquiry module in vehicle is shown in Figure 1 contains a switch/button, ZigBee module, and liquid crystal display (LCD). The parking inquiry module is integrated in the vehicle, when the person in the vehicle wants to know the information about the free parking slots then he will press the in the vehicle; then a request through ZigBee goes to button the monitor system in the parking section as shown in Figure 2 about the free parking space. The parking monitor system upon request from vehicles inquiry, it sends a message to the vehicle using ZigBee, whether the parking is available or not and is displayed on LCD.
Fig. 1. A parking Inquiry module inside a vehicle
B. Parking Monitor System The parking monitor system is shown in Figure 2 with and RF communicating devices. On receiving the ZigBee message from vehicle section, the parking monitor system intimates the vehicle using ZigBee whether the parking is empty or full by collecting the status from parking slot detector, which is equipped in second floor. Primarily, the parking monitor system checks the availability for free space in first floor and if it is unavailable then it checks the availability in second floor. The RF Receiver (RF RX) in parking monitor system receives the information uninterruptedly from parking slot detector, which maintains an up-to-date status of parking availability with exact slot. The communication between parking monitor system and parking slot detector is through RF. The RF communication is with a frequency range of 900 MHz, which allows the coverage area up to 15.2m (50 feet). The IR sensors are used to detect the vacant position and the information is sent to ARM microcontroller. Thus the parking monitor system knows the exact parking slots available and then finally it
00-5/15/$31.00978-1-4673-7300-5/15/$31.00 ©2015 IEEE ©2015 IEEE
Fig. 2. A parking monitor system
C. Parking Slot Detector The parking slot detector, which is shown in Figure 3 is installed or equipped in second floor. The information of exact free space for parking is known through IR sensors. If any parking slot has no vehicle then the IR sensor detects and informs to the ARM 7 microcontroller and is displayed on LCD. IR sensors are cheap and are accurate to detect the surroundings by emitting and/or detecting infrared radiation. The parking slot detector includes RF Transmitter (RF TX) to send the information continuously to parking monitor system. The communication is reliable and the information is errorfree. If it detects any parking slot, then it sends that message to parking monitor system with exact slot information and if there is no availability then it sends a “No Vacant” message. Thus it takes complete control on second floor without the intervention of parking monitor system and so it is capable to reduce the responsibilities of monitoring system to some extent. However, the parking availability to vehicle section is informed only through parking monitor system. Finally, the proposed system can identify the parking availability and thus it informs the vehicle with available parking in floor and slot details and if there is no space available, then it sends as a message like “No parking availability” by parking monitor system. Thus the vehicle owner can understand the status and thus takes a decision for parking which saves time, fuel, reduced pollution effect and thus money. The system can be extended to any number of floors with the addition of parking slot detectors and can be even monitored with a single parking monitor system.
Fig. 3. A parking slot detector
Proceedings of the IEEE SoutheastCon 2015, April 9 - 12, 2015 - Fort Lauderdale, Florida
D. Work-Flow of the Proposed System The work-flow of the proposed system is shown step by step in Figure 4. Floor 1 has the RF receiver module and it the parking availability status from Floor 2, which receives has RF transmitter. When Floor 1 gets a signal from a car ZigBee it gives the availability of parking status with through location and floor address by using ZigBee module to vehicle. Floor 1 receives the status of Floor 2 continuously through RF communication, which is very reliable. The process is repeated for every request from a vehicle serially to eliminate traffic. The proposed system is implemented using ZigBee communication standard to save energy as it is always an overloaded scenario to find the parking space. The data size is so small (
