Abstract:
A communication system for a climate-controlled container. The system includes a controller and a radio expansion module removably connected to the controller. The controller is coupled to the refrigerated container and configured to monitor a status of the refrigerated container. The radio expansion module is configured to support a communication mode, and to communicate the status to a remote system. The communication mode used to communicate with the remote system is determined by the controller based on the communication modes supported by the radio expansion module.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to communication systems for refrigerated transportation containers. 
       BACKGROUND 
       [0002]    Climate-controlled transportation containers, such as refrigerated trailers, refrigerated containers, and refrigerated trucks, are used for transporting goods that must be kept below a certain temperature to prevent spoilage. Often the refrigerated transportation containers monitor the status of environmental conditions of the container and communicate the status to a remote location along with other information, such as the location of the container. Because different fleet operators have different communication preference and/or needs, manufacturers of refrigerated transportation containers must customize the containers for each fleet operator to meet the individual communication needs of the operator. 
       SUMMARY 
       [0003]    In one embodiment, the invention provides a communication system for a climate-controlled container. The system includes a controller and a radio expansion module removably connected to the controller. The controller is coupled to the climate-controlled container and configured to monitor a status of the refrigerated container. The radio expansion module is configured to support a communication mode, and to communicate the status to a remote system. The communication mode used to communicate with the remote system is determined by the controller based on the communication modes supported by the radio expansion module. 
         [0004]    In another embodiment the invention provides a communication system including a controller, a first radio expansion module, and a second radio expansion module. The controller is coupled to a device to be monitored, and is configured to monitor a status of the device. The first radio expansion module is configured to be removably connected to the controller, and to communicate the status to a remote system via a first communication mode. The second radio expansion module is configured to be removably connected to the controller, and to communicate the status to the remote system via a second communication mode. 
         [0005]    In another embodiment the invention provides a method of communicating by a communication controller with a remote system. The method includes the acts of connecting to a removable radio expansion module populated with a plurality of circuits for communicating, obtaining data from a device external to the communication controller, determining a communication mode to use to send the data to the remote system, and sending the data to the remote system via the radio expansion module using the determined communication mode. Each of the plurality of circuits for communicating provides a different communication mode. 
         [0006]    In another embodiment the invention provides a communication system for a climate-controlled container. The system includes a controller and a radio expansion module. The controller is coupled to the climate-controlled container and is configured to monitor a status of the refrigerated container. The radio expansion module is removably connected to the controller and is configured to support a plurality of communication modes including at least two of cellular, satellite, and WiFi. The radio expansion module is also configured to communicate the status to a remote system. When a WiFi communication link is available, and the radio expansion module is configured to support a WiFi communication mode, the controller communicates with the remote system via a WiFi communication link. When a WiFi communication link is not available, or the radio expansion board is not configured to support a WiFi communication mode, and a cellular communication link is available, and the radio expansion board is configured to support a cellular communication mode, the controller communicates with the remote system via a cellular communication. 
         [0007]    Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is an illustration of a variety of communication links available for use by constructions of a configurable communication system. 
           [0009]      FIG. 2  is a block diagram of a configurable communication system. 
           [0010]      FIG. 3  is a block diagram of a radio expansion module of the configurable communication system of  FIG. 3 . 
           [0011]      FIG. 4  is a flow diagram of an operation of the configurable communication system of  FIG. 3  for communicating to a remote system. 
           [0012]      FIG. 5  is a flow diagram of an operation of an exemplary remote system for communicating to a refrigerated container having a configurable communication system. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Before any embodiment of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiment and of being practiced or of being carried out in various ways. 
         [0014]      FIG. 1  shows a semi-trailer truck  200  with a refrigerated trailer  205  which is monitored and controlled by a remote system  210  (e.g., a workstation). The remote system  210  receives data from the refrigerated trailer  205  either by polling the refrigerated trailer  205 , by unsolicited communication from the refrigerated trailer  205  (e.g., on a timed basis or as a result of an alarm condition), or both. 
         [0015]    The refrigerated trailer  205  is equipped with a configurable communication system, and can use one or more communication modes to communicate with the remote system  210 . For example, the trailer  205  can communicate via a cellular link  215 , a satellite link  220 , a WiFi link  225  (e.g., via a router  230 ), a wireless personal area network (WPAN) link  235  (e.g., to a personal data assistant  240 ), or other suitable communication link. The remote system  210  can communicate via a cellular link  245 , a satellite link  250 , a WiFi link  255 , a land-line telephone link  260 , or other suitable communication methods including links not shown, such as a direct connection (e.g., RS232), an infrared link, a radio frequency (RF) link, and other third-party telematics links. 
         [0016]    The trailer  205 , via the configurable communication system, determines which communication mode to use based on a criterion. Potential criteria include signal strength, cost, integrity of the mode, and security of the mode. For example, a refrigerated trailer  205  with a configurable communication system that is configured to use cellular, satellite, and WiFi communication modes, can select cellular communication when on the road in an area having cellular service (i.e., when a cellular link is available), cellular communication being generally cheaper than satellite communication. However, should the trailer  205  be loaded on a barge that is at sea, cellular communication would not be available; therefore, the trailer  205  would communicate using satellite communication. Further, when the trailer  205  is located at a terminal, the trailer  205  would communicate using WiFi because there would be no charges associated with the WiFi communication. However, if the communication included sensitive information, and the WiFi system is unsecured, the trailer  205  could communicate using an alternative communication mode. In addition, a user  265  could communicate with the trailer  205  using the WiFi communication via a personal data assistant  240  (e.g., through a wireless router  230 ). 
         [0017]    Data that the system  210  receives from the refrigerated trailer  205  includes, but is not limited to, the trailer&#39;s present position, a speed of the trailer, a temperature set point in the trailer, a return air temperature, a discharge air temperature, an operating mode, a unit mode, an alarm status, an hours of operation indication, a fuel quantity, a fuel consumption rate and total, a status of a door, a battery voltage, and other sensed information. Commands that are sent from the system  210  to the refrigerated trailer  205  include, but are not limited to, changing a temperature set point, resetting an alarm, and reprogramming a flash memory (the command can include a program to replace the program presently running in the configurable communication system). 
         [0018]      FIG. 2  shows a block diagram of a construction of a configurable communication system  300  for a refrigerated transport container (e.g., a refrigerated trailer). The configurable communication system  300  includes a controller  305  and a radio expansion module  310 . The radio expansion module  310  is removably connected to the controller  305 . That is the radio expansion module  310  can be easily (or readily) removed and replaced by another radio expansion module  310 . In some constructions, the radio expansion module  310  is held in place by one or more fasteners (e.g., screws). In some constructions, the radio expansion module  310  includes a spring biased latch to hold the radio expansion module  310  in place. Other methods of securing the radio expansion module  310  in place are also contemplated. The radio expansion module  310  has a connector  315  (e.g., a card edge connector) for connecting to a receiver  320  of the controller  305 . In some constructions, the radio expansion module conforms to the PCMCIA specification. The invention contemplates other methods of connecting the radio expansion module  310  to the controller as well including, but not limited to, a socket, a cable (e.g., USB, RS232, etc.), etc. When installed, the radio expansion module  310  is held in place such that it will not separate from the controller  305  when the container is being transported. However, an operator can remove the radio expansion module  310  from the controller  305  and replace the radio expansion module  310  with another radio expansion module  310  (e.g., to replace a faulty radio expansion module  310  or to install a radio expansion module  310  having different capabilities). 
         [0019]    The controller  305  is connected to a refrigeration unit of the container. The refrigeration unit controls the environment inside the container. In some constructions, the system  300  includes a global positioning system (GPS). The GPS can be included in the controller  305 , the radio expansion module  310 , or the refrigerated trailer  205 . The controller  305  receives power from the refrigeration unit and monitors the status of the refrigeration unit and the container. In some embodiments, information received from the refrigeration unit and/or container includes the present position of the container, a speed of travel of the container, a temperature set point of the container, a return air indication (e.g., volume, temperature, etc.), a discharge air indication, an operating mode of the refrigeration unit, alarm indications, an hour meter indication, refrigeration unit and/or container sensor data, a fuel quantity of the refrigeration unit, a fuel consumption indication, a container door status, a voltage level of one or more batteries of the refrigeration unit, etc. 
         [0020]      FIG. 3  shows a block diagram of a construction of the radio expansion module  310 . The module  310  includes a processing circuit  400 , a third-party telematics interface  405  (e.g., a USB interface, an RS232 interface, a RS422 interface, etc.), an input/output circuit  407  (e.g., digital and/or analog), a global positioning system circuit (GPS)  408 , and one or more communication circuits such as a first communication circuit  410 , a second communication circuit  415 , and a third communication circuit  420 . The processing circuit  400  includes a processor  425  (e.g., a microprocessor, microcontroller, ASIC, DSP, etc.) and memory  430  (e.g., flash, ROM, RAM, EEPROM, etc.), which can be internal to the processor  425 , external to the processor  425 , or a combination thereof. In some constructions, the processor  425  includes the input/output circuit  407  and/or the GPS  408 . The first, second, and third communication circuits  410 ,  415 , and  420  provide the communication system  300  with communication capabilities such as cellular, satellite, WiFi, RS232, WPAN, infrared, radio frequency (RF), etc. In the construction shown, each radio expansion module  310  is configured with up to three communication modes. If less than three communication modes are required, one or more of the communication circuits  410 ,  415 , and  420  are not populated. The communication circuits  410 ,  415 , and  420  can include an embedded antenna or can be coupled to an external antenna. In some constructions, two or more communication circuits share an external antenna. 
         [0021]    In some constructions, sensors in the container  205  are wired to the input/output circuit  407 . The processor  425  receives indications of the status of various elements of the container (e.g., whether a door of the container  205  is open or closed) from the sensors. 
         [0022]    In some constructions, one of the communication circuits is populated to communicate with a WPAN (e.g., via Bluetooth). The WPAN communicates with devices near or in the container  205 , and retrieves information from various sensors, and switches, such as the status of doors (e.g., a fuel door). In some constructions, the personal area network provides information to a human machine interface in a driver&#39;s compartment of a truck (e.g., showing the temperature of the container, fuel level, alarms, etc.). 
         [0023]    In some embodiments, the communication circuit functions as a web server and provides data via the Internet. Also, in some embodiments, the communication system  300  may communicate with the remote system  210  via multiple communication modes simultaneously (e.g., to communicate a critical alarm condition). 
         [0024]      FIG. 4  shows an operation for a trailer  205  initiating communication with a remote system  210  (e.g., to send a status update or an alarm). The controller  305  of the trailer  205  analyzes the communication that is taking place to determine the communication requirements (step  500 ). For instance, the controller  305  determines if the communication includes sensitive data, the size of the communication packets, the importance of the data, etc., and then determines what communication links are acceptable for the data. Next, the controller  305  determines what communication modes are available (i.e., populated) on the radio expansion module  310  (step  505 ), and the status of each loaded communication mode (step  510 ). For example, the radio expansion module  310  determines the availability and signal strength for each available mode, providing that information to the controller  305 . The controller  305  and the radio expansion module  310  can also track the various signals to determine the likelihood of losing a connection. Based on the communication taking place and the status of the various modes, the radio expansion module  310  ranks the available communication modes (step  515 ). For example, the radio expansion module  310  may rank the communication modes based on cost for a lengthy communication with data that does not need to be secure. For data that needs to be secure, the controller  305  may rule out the use of an unsecured WiFi communication mode. The controller  305  then selects the highest ranked mode and attempts to connect to the remote system  210  (step  520 ). 
         [0025]    If a connection is made (step  525 ), the radio expansion module  310  executes the communication (step  530 ). If the radio expansion module  310  is unable to connect to the remote system  210  via the chosen communication mode (step  525 ), the radio expansion module  310  determines if another acceptable communication mode is available (step  535 ); and if there is, attempts to connect to the remote system  210  using the next highest ranked available mode (step  520 ). If no other acceptable mode is available, the radio expansion module  310  either attempts to connect with a previously attempted mode or exits (step  540 ) the process. In some constructions, when a connection cannot be made, the radio expansion module  310  provides an alarm indication (e.g., to a driver who can then perform a corrective procedure). In some constructions, when a connection cannot be made, the radio expansion module  310  stores data and forwards the data once a reliable connection is available. 
         [0026]      FIG. 5  shows an operation for a central office (i.e., the remote system  210 ) initiating communication with a refrigerated trailer  205  (e.g., to receive a status update or to modify a temperature set point). The system  210  analyzes the communication that is taking place (step  600 ). For instance, the system  210  determines if the communication includes sensitive data, the size of the communication packets, how important the data is, etc. Based on the communication taking place, the system  210  then ranks the available communication modes (step  605 ). For example, the system  210  may rank the communication modes based on cost for a lengthy communication with data that does not need to be secure. For data that needs to be secured, the system  210  may rule out the use of an unsecured WiFi communication mode. For downloading a new program to the trailer  205 , where data loss must be prevented, the system  210  may rank the communication modes based on the integrity of the mode. Once the communication modes are ranked for the pending communication, the system  210  determines what communication modes are available on the trailer  205  that it is attempting to communicate with (step  610 ). The system  210  then determines if any of the available communication modes are acceptable (step  615 ). If there are no acceptable communication modes available, the system  210  ends the process (step  620 ). If one or more acceptable communication modes are available, the system  210  selects the highest ranked mode that the trailer  205  supports, and attempts to connect to the trailer  205  (step  625 ). 
         [0027]    If a connection is made (step  630 ), the system  210  executes the communication (step  635 ). If the system  210  is unable to connect to the trailer  205  via the chosen communication mode (step  640 ), the system  210  determines if there is another acceptable communication mode (step  645 ), and if there is, attempts to connect to the trailer  205  using the next highest ranked available mode (step  625 ). If no other acceptable mode is available, the system  210  either attempts to connect with a previously attempted mode or exits the process (step  620 ). In a case where a connection cannot be made, the system  210  may provide an alarm indication to a user who can then attempt to contact the driver or execute another procedure. 
         [0028]    Thus, the invention provides, among other things, a new and useful configurable communication system for refrigerated containers. Various features and advantages of the invention are set forth in the following claims.