Patent Grant
6862433
1. Field of the Invention
This invention relates in general to antenna systems and in particular to antenna systems for wireless information devices.
2. Description of the Related Art
The digital age has brought with it an abundance of options and availability of electronic information. Along with this explosion in electronic information is the availability of portable devices for using this information. For example, electronic books provide users with high quality electronic editions of books, magazines and newspapers. Users download over phone lines thousands of titles from the Internet site of the electronic book providers. As another example, portable web browsers provide users with access to the growing Internet sites to quickly and easily obtain whatever information they require wherever the user is and whenever it is needed usually via conventional telephone lines. The growing market for such portable electronic information devices has led to a growing popularity of wireless information. Wireless information devices allow the user the flexibility of access to the electronic information they desire or require without the additional requirement of telephone landline access.
Wireless information devices such as wireless web browsers and wireless electronic books can be used in multiple physical orientations relative to the user's body. The device can be oriented in the landscape format (short display side vertical), for such activities as web browsing or viewing slides, and then rotated to the portrait format (long display side vertical), for such activities as reading email or reading an electronic book. For maximum reading flexibility, some non-wireless electronic books allow the user to rotate the image in steps of ninety degrees so that, for example, the same side of the device can be held in either hand while reading.
Antenna design creates a challenge for the product designer of wireless information devices used for wireless web browsing or wireless electronic books. Since antenna performance is greatly dependent on the antenna's physical relationship with the body, achieving consistent antenna performance under the conditions surrounding the use of wireless information devices is challenging. No matter where the antenna is placed, depending upon the user's utilization of the product, the antenna can end up under the user's hand, or pressed against the body, resulting in reduced antenna performance.
One conventional approach to this design challenge is the use of antenna diversity. Antenna diversity involves choosing the best signal, or combination of signals, received from multiple antennas. One of the difficulties of this approach in portable products, getting enough space inside the product for the extra antennas, is less of a concern with wireless information devices, due the their relatively large size. However, diversity also requires additional power for the duplicate receiver signal paths required, and this can significantly affect product battery life. The addition of a duplicate receiver can also increase manufacturing cost of the device. There is also additional signal quality estimation that must be performed on the signal from each antenna. Lastly, a scheme for the choice of the proper transmit antenna is required. For these reasons, antenna diversity is not an optimum solution to this problem.
Alternatively, the product designer can either accept a reduction in wireless performance for some orientations of the wireless information device, or eliminate the ability for users to orient the wireless information device in the multiple orientations providing the most ergonomically pleasing orientation for each of a multiplicity of functions. Both of these options can reduce the utility and/or desirability of the wireless information device.
What is needed is an antenna system that allows the user to orient the wireless information device relative to the user's body in a multiplicity of orientations with consistent product performance without additional cost or size to the product.
Referring to
The system controller 22 is coupled to and oversees the operation of at least one radio frequency (RF) transmitter 24 and at least one radio frequency (RF) receiver 26 through one or more communication links 28. The communication links 28 typically are twisted pair telephone wires, and additionally can include radio frequency (RF), microwave, or other communication links. The radio frequency transmitter 24 and the radio frequency receiver 26 typically are used with message store and forward stations that encode and decode inbound and outbound messages into formats that are compatible with landline message switched computers and personal radio addressing requirements, such as cellular messages, short messaging service, or paging protocols. The system controller 22 can also perform other functions; for example, it can encode and decode wireless messages that are transmitted to or received by the radio frequency transmitter 24 or the radio frequency receiver 26. Telephony signals are typically transmitted to and received from the system controller 22 by telephone sets such as the telephone 12 or a wireless information device 30. The system controller 22 encodes and schedules outbound messages such as a message 32 or an information message 34. The system controller 22 then transmits the encoded outbound messages through the radio frequency transmitter 24 via a transmit antenna 36 to a plurality of wireless information devices 38 such as a wireless information device 30 on at least one outbound radio frequency (RF) channel 40. The message 32 or the information message 34 can be, for example, a data message or a voice call. Similarly, the system controller 22 receives and decodes inbound messages such as an acknowledgement message 42 or a query message 44 received by the radio frequency receiver 26 via a receive antenna 46 on at least one inbound radio frequency (RF) channel 48 from one of the plurality of wireless information devices 38. The acknowledgement message 42 or the query message 44 can be, for example, a data message, a reply to a data message, a voice call, or a reply to a voice call.
It will be appreciated by one of ordinary skill in the art that the wireless information communication system 10, in accordance with the present invention, can function utilizing any wireless RF channel, for example, a one- or two-way pager channel, a mobile cellular telephone channel, or a mobile radio channel. Similarly, it will be appreciated by one of ordinary skill in the art that the wireless information communication system 10 can function utilizing other types of communication channels such as infrared channels. In the following description, the term “wireless information communication system” refers to any of the wireless information communication systems mentioned above or an equivalent.
Similarly, it will be appreciated by one of ordinary skill in the art that the wireless information device 30 in accordance with the present invention, can be a mobile cellular telephone, a mobile radio data terminal, a mobile cellular telephone having an attached data terminal, or a two-way pager, such as the “Pagewriter 2000X” manufactured by Motorola Inc. of Schaumburg, Ill. In the following description, the term “wireless information device” refers to any of the devices mentioned above or an equivalent.
The wireless information device 30 assigned for use in the wireless information communication system 10 has an address 50 or identity assigned thereto which is a unique selective call address in the wireless information communication system 10. It will be appreciated by one of ordinary skill in the art that other wireless information devices assigned for use in the wireless information communication system 10 have an address assigned thereto which is a unique selective call address in the wireless information communication system 10.
The address 50 enables the transmission of the message 32 or the information message 34 from the system controller 22 only to the wireless information device 30 having the address 50, and identifies the messages and responses such as the acknowledgement message 42 or the query message 44 received at the system controller 22 from the wireless information device 30 with the address 50. In one embodiment, each of the plurality of wireless information devices 38 also has a pin number assigned thereto, the pin number being associated with a telephone number within the PSTN 18. A list of the assigned addresses and correlated telephone numbers for each wireless information device 30 is stored in the system controller 22 in the form of a subscriber database 52.
In a preferred embodiment of the present invention, the wireless information communication system 10 includes an information server 54 coupled to the system controller 22 via a server interface 56. The information server 54 controls and manages communication of a plurality of information content 58 to the plurality of wireless information devices 38 by sending wireless messages to the plurality of wireless information devices 38. The information content 58 can be, for example, electronic books, Internet web page information, or the like. The addition of the information server 54 to the wireless information communication system 10 enhances the operation of the wireless information communication system 10 by adding intelligence for the management of the information content 58 including the communication among and to the plurality of wireless information devices 38.
Referring to
The system controller 22 is coupled to and oversees the operation of at least one radio frequency (RF) transmitter 24 and at least one radio frequency (RF) receiver 26 through one or more information communication links 61. The information communication links 61 typically are metallic connections on a printed circuit board or integrated circuit, and additionally can include radio frequency (RF), microwave, or other communication links. The radio frequency transmitter 24 and the radio frequency receiver 26 typically encode and decode inbound and outbound messages into formats that are compatible with landline packet switched computers and personal radio addressing requirements, such as Wireless Personal Area Networks (WPANs) or Wireless Local Area Networks (WLANs). Examples of WPANs are networks based on the Bluetooth, HomeRF, and IEEE 802.15.3 protocols; examples of WLANs are networks based on the Hiperlan 2, IEEE 802.11a, and 802.11.b protocols. The system controller 22 can also perform other functions; for example, it can encode and decode wireless messages that are transmitted to or received by the radio frequency transmitter 24 or the radio frequency receiver 26. Telephony signals are typically transmitted to and received from the system controller 22 by the computer network 59 or the wireless information device 30. The system controller 22 encodes and schedules outbound messages such as the message 32 or the information message 34. The system controller 22 then transmits the encoded outbound messages through the radio frequency transmitter 24 via a transmit antenna 36 to the plurality of wireless information devices 38 such as the wireless information device 30 on at least one outbound radio frequency (RF) channel 40. The message 32 or the information message 34 can be, for example, a data message or a voice call. Similarly, the system controller 22 receives and decodes inbound messages such as the acknowledgement message 42 or the query message 44 received by the radio frequency receiver 26 via the receive antenna 46 on at least one inbound radio frequency (RF) channel 48 from one of the plurality of wireless information devices 38. The acknowledgement message 42 or the query message 44 can be, for example, a data message, a reply to a data message, a voice call, or a reply to a voice call.
It will be appreciated by one of ordinary skill in the art that the wireless information communication system 10, in accordance with the present invention, can function utilizing any wireless RF channel, for example, a one or two-way pager channel, a mobile cellular telephone channel, a WPAN or WLAN channel, or a mobile radio channel. Similarly, it will be appreciated by one of ordinary skill in the art that the wireless information communication system 10 can function utilizing other types of communication channels such as infrared channels. In the following description, the term “wireless information communication system” refers to any of the wireless information communication systems mentioned above or an equivalent.
It will be appreciated by one skilled in the art that the antenna system 62 in accordance with the present invention can be formed as described herein or in an equivalent manner. For example, the antenna system 62 as illustrated in
Referring to
The antenna system 62 intercepts transmitted signals from the wireless information communication system 10. The antenna system 62 is coupled to the transceiver 82 through the RF switch 80. The transceiver 82 employs conventional demodulation techniques for receiving the communication signals transmitted by the wireless information communication system 10 such as the message 32 or the information message 34 of FIG. 1. Further, the transceiver 82 is responsive to commands from the controller 84. When the transceiver 82 receives a command from the controller 84, the transceiver 82 sends a signal via the antenna system 62 to the wireless information communication system 10 such as the acknowledgement message 42 or the query message 44 (see FIG. 1).
In an alternative embodiment (not shown), the wireless information device 30 includes a receiver circuit and a transmitter circuit for performing the functionality of the transceiver 82. It will be appreciated by one of ordinary skill in the art that other similar electronic block diagrams of the same or alternate type can be utilized for the wireless information device 30 to handle the requirements of the transceiver 82.
Coupled to the transceiver 82 is the controller 84 utilizing conventional signal processing techniques for processing received messages. Preferably, the controller 84 is similar to the MC68328 micro-controller manufactured by Motorola, Inc. of Schaumburg, Ill. It will be appreciated by one of ordinary skill in the art that other similar processors can be utilized for the controller 84, and that additional processors of the same or alternative type can be utilized as required to handle the processing requirements of the controller 84.
The controller 84 decodes an address in the demodulated data of the received message, compares the decoded address with one or more addresses such as the address 50 stored in an address memory 100 of the memory 86; and when a match is detected, proceeds to process the remaining portion of the received message.
To perform the necessary functions of the wireless information device 30, the controller 84 is coupled to the memory 86, which preferably includes a random access memory (RAM), a read-only memory (ROM), and an electrically erasable programmable read-only memory (EEPROM)(not shown). The memory 86 also includes the address memory 100, a message memory 102, and an information memory 104.
Once the controller 84 has processed a received message such as the message 32, it stores the decoded message in the message memory 102. The received message, for example, can be a notification of an update to a web page ready for download or a notification of the availability of a new electronic book. It will be appreciated by one of ordinary skill in the art that the message memory 102, in accordance with the present invention, can be a voicemail box or a group of memory locations in a data storage device. In the following description, the term “message memory” refers to any of the memory means mentioned above or an equivalent.
Once the controller 84 has processed a received information message such as the information message 34, it stores the decoded information included in the information message 34 in the information memory 104. The decoded information can be, for example, an electronic book, a web page, or an Internet document. It will be appreciated by one of ordinary skill in the art that the information memory 104, in accordance with the present invention, can be a group of memory locations in a data storage device. In the following description, the term “message memory” refers to any of the memory means mentioned above or an equivalent.
Upon receipt and processing of the message 32 or the information message 34, the controller 84 preferably generates a display command 94 to the display 60 to generate a visual notification of the receipt and storage of the message or the information. When the display 60 receives the display command 94 from the controller 84 that the message has been received and stored, a message indication is displayed. The message indication, for example can be the activation of one of a plurality of message icons on the display 60. The display 60 can be, for example, a liquid crystal display utilized to display text. It will be appreciated by one of ordinary skill in the art that other similar displays such as dot matrix displays can be utilized for the display 60.
Alternatively, upon receipt and processing of the message 32 or the information message 34, the controller 84 generates the display command 94 to the display 60 to generate a visual image substantially representing at least a portion of the information received in the message 32 or the information message 34.
Upon receipt and processing of the message 32 or the information message 34, the controller 84 preferably also generates a command signal to the alert circuit 106 to notify the device user that the message has been received and stored. The alert circuit 106 can include a speaker (not shown) with associated speaker drive circuitry capable of playing melodies and other audible alerts, a vibrator (not shown) with associated vibrator drive circuitry capable of producing a physical vibration, or one or more LEDs (not shown) with associated LED drive circuitry capable of producing a visual alert. It will be appreciated by one of ordinary skill in the art that other similar alerting means as well as any combination of the audible, vibratory, and visual alert outputs described can be used for the alert circuit 106.
Preferably, the user interface 108 is coupled to the controller 84, as shown in FIG. 4. The user interface 108 can be one or more buttons used to generate a button press, a series of button presses, a voice response from the device user, or some other similar method of manual response initiated by the device user of the wireless information device 30. The controller 84 is responsive to signals received from the user interface 108.
Upon receipt of a user interface signal 110 from the user interface 108, including instructions to display a particular information data stored in the message memory 102 or in the information memory 104, the controller 84 is programmed to send the display command 94 to the display 60 including a plurality of displayed data 96 received in the message 32 or information message 34 and stored in the message memory 102 or in the information memory 104. The display 60, in response to receipt of the plurality of displayed data 96, generates a visual display that substantially represents at least a portion of the information.
Upon receipt of the user interface signal 110 from the user interface 108, including instructions to query the information server 54 of
To perform the necessary functions of the wireless information device 30, the controller 84 is coupled to the RF switch 80. The controller 84 controls the RF switch 80 by sending an antenna control signal 98 to the RF switch 80. Upon receipt of the antenna control signal 98, the RF switch 80 determines which of the multiple antennas of the antenna system 62 is an active antenna 116. The antenna switching of the antenna system 62 is preferably based on factors other than qualities of the radio frequency communications link.
In one embodiment, the user-controlled display rotation switch 88 is coupled to the controller 84. The device user opens and closes the user-controlled display rotation switch 88 dependent upon which orientation of the display 60 is desired and/or required. In other words, the user-controlled display rotation switch 88 changes modes from open to close or from close to open dependent upon which orientation of the display 60 is desired and/or required. In response, the controller 84 sends a display orientation control signal 112 to the display 60. In response to receipt of the display orientation control signal 112, the display 60 modifies its display orientation. Further, the controller 84 sends the antenna control signal 98 to the RF switch 80 identifying the new display orientation. The RF switch 80, in response to receipt of the antenna control signal 98, switches which of the plurality of antennas of the antenna system 62 is the active antenna 116 to the one most likely to have optimum performance.
Alternatively, the orientation sensor 92 is coupled to the controller 84. The orientation sensor 92 determines the orientation of the display 60 and notifies the controller 84 accordingly. In response, the controller 84 sends the antenna control signal 98 to the RF switch 80 identifying the display orientation. The RF switch 80, in response to receipt of the antenna control signal 98, switches which of the plurality of antennas of the antenna system 62 is the active antenna 116 to the one most likely to have optimum performance. Typically, the antenna of the antenna system 62 located at the top of the display 60 based on the display orientation is chosen as the active antenna 116, that being the antenna most likely to be free of the hands and away from the body. Preferably, the orientation sensor 92 is sensitive to gravity and can be, for example, a set of mercury switches that determine the direction of “up” and “down”. It will be appreciated by one of ordinary skill in the art that other similar gravity sensitive detection means, as well as other orientation determination means, can be used for the orientation sensor 92. It will be appreciated by one skilled in the art that a certain amount of hysteresis would be needed to control unnecessary switching between antennas in certain orientations (i.e.: when the wireless information device 30 is lying flat on a table).
Alternatively, the plurality of hand sensors 90 is coupled to the controller 84. Each of the plurality of hand sensors 90 can be, for example, capacitive sensors or phototransistors. It will be appreciated by one of ordinary skill in the art that other similar hand sensor means as well as any combination of those described can be used for the plurality of hand sensors 90. Each of the plurality of hand sensors 90 is placed near each antenna. The controller 84 receives a signal from each of the plurality of hand sensors 90 indicating the amount of obstruction related to the associated antenna. The controller 84 then chooses the antenna with the hand sensor indicating the least obstruction (the lowest capacitance or the most light, relative to the other sensors in the wireless information device 30) to be the active antenna 116. It will be appreciated by one skilled in the art that a certain amount of hysteresis would be needed to control undesired switching between two antennas with similar sensor values. The controller 84 then sends the antenna control signal 98 to the RF switch 80 identifying the active antenna 116. The RF switch 80, in response to receipt of the antenna control signal 98, switches the active antenna 116 of the antenna system 62 to the one most likely to have optimum performance as specified by the controller 84.
It will be appreciated by one skilled in the art that the controller 84 can combine the methods described herein to determine the optimum antenna to be utilized. For example, the controller 84 can use the display orientation method to make a decision if the spatial orientation method provides indeterminate results (i.e.: when the wireless information device 30 is lying flat on a table).
The user may, through a “preferences” entry of the user interface 108, modify the above antenna selection criteria to cover special circumstances. For example, the user may wish to modify the hand detection algorithm under unusual lighting conditions, if the phototransistor method of hand detection is used.
Referring to
In Step 130, when either the user controlled display rotation switch 88 is utilized in Step 124, or the orientation sensor 92 is active in Step 126, or the plurality of hand sensors 90 are active in Step 128, the controller 84 determines whether it has been programmed to combine some combination of these inputs. In Step 132, when a combination is required or desired, the controller 84 combines inputs from more than one of the inputs. Next, in Step 134, and when no combination is required or desired in Step 130, and also when the user preference is used from Step 122, the controller 84 sends the antenna control signal 98 to the RF switch 80.
The present invention, as described herein provides an efficient and effective antenna system for use with a wireless information device. The present invention provides, within the wireless information device, a method and apparatus for automatically switching between a plurality of antennas each oriented in a different direction to provide enhanced communications performance within a wireless communication system.
Although the invention has been described in terms of preferred embodiments, it will be obvious to those skilled in the art that various alterations and modifications may be made without departing from the invention. Accordingly, it is intended that all such alterations and modifications be considered as within the spirit and scope of the invention as defined by the appended claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 5373300 | Jenness et al. | Dec 1994 | A |
| 5737690 | Gutman | Apr 1998 | A |
| 6150984 | Suguro et al. | Nov 2000 | A |
| 6285893 | Keirinbou | Sep 2001 | B1 |
| 6411826 | Camp, Jr. | Jun 2002 | B1 |
| 6498589 | Horii | Dec 2002 | B1 |
| 20020111194 | Behbahani et al. | Aug 2002 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20020106995 A1 | Aug 2002 | US |
