Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/08—Means for collapsing antennas or parts thereof
  • H01Q1/084—Pivotable antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/12—Supports; Mounting means
  • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
  • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
  • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
  • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
  • H01Q1/245—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with means for shaping the antenna pattern, e.g. in order to protect user against rf exposure

Definitions

• the invention relates to an antenna device at a mobile terminal, in the first place a hand portable terminal arranged to be connected to a telecommunication network for mobile telecommunication, for instance a cellular mobile telephone network.
• a hand portable terminal arranged to be connected to a telecommunication network for mobile telecommunication, for instance a cellular mobile telephone network.
• a telecommunication network for mobile telecommunication for instance a cellular mobile telephone network.
• patent application JP 730 7607 is described a telescopic antenna (rod antenna) to a mobile terminal where the antenna can be bent in a joint. By this maneuver the radiation effect of the antenna at use can be directed away from the head in order to by that reduce the injure which the radiation might cause to close located parts of the head.
• EP 806 809A1 has in the patent application EP 806 809A1 been described a mobile terminal which is equipped with a rod antenna which is articulated mounted in the upper side of the mobile terminal. A screening covering covers the point of attachment and the joint.
• the antenna can at use of the mobile terminal be angled from the head in order to by that reduce the radiation which is directed towards the head. By the antenna being angled from the head, the radiation levels directed towards the head are expected to fall below the threshold values which have been set by the health department of the Peoples Republic of China.
• Helix antennas also called stub antennas, which are common on mobile terminals, by that cause considerable problems since these have poorer communication qualities than the longer, usually extensible, rod antennas. This is especially noticeable at the outer fringe of the coverage area of base stations, in houses and in cars without external antenna.
• the main reason for the voice quality of a mobile terminal having a stub antenna (helix antenna) being so much poorer than if the same terminal was equipped with an antenna with a longer rod (half wave antenna) is that the stub antenna is influenced considerably more by the user' s head than the rod antenna is. It is important that the impedance in the radio part of the terminal and antenna match each other because the signal from the radio part shall meet a constant load to achieve best effect at the transmission. Antennas therefore are designed to function as a 50 ⁇ -load for the radio part.
• the terminal when used, is held to the ear, there is a coupling between the antenna of the terminal and the tissue of the user's head and hand. In that way a part of the signal is reflected back into the antenna, at which the load, and by that the output power, starts varying.
• the smaller the distance between antenna and the head the stronger the coupling between the antenna and the head.
• said distance is of the size cm, the coupling is considerably changed if the terminal is moved some mm, at which the transmitted power from the terminal is noticeably influenced. This also means that said coupling becomes larger at smaller antennas, such as stub antennas, which, during conversation, have all their extent in the surroundings of the user's head.
• the antenna function at a mobile terminal which is held at the ear is influenced by the user's head and hand. This influence on the antenna results in that a large portion of the to the antenna fed output power is lost as heating power in head, hand and in the terminal. By a large portion of the power being lost, the efficiency of the antenna is reduced, at which more transmission power must be used.
• the communication possibilities will instead be influenced, which is experienced by the user as deteriorated quality.
• the location of base stations is to a large extent influenced by the range of the mobile terminals.
• a limited range by that means that the operator has to make a big investment in infrastructure. If, on the other hand, the range can be increased, said investment can be limited.
• An improved antenna efficiency of the mobile terminal consequently implies that it is possible for an operator to reduce the costs for network extension, since the need for density of base stations will be reduced.
• the easiness to handle a mobile terminal is to a great extent influenced by the on the terminal existing antenna.
• a protruding antenna often results in that the terminal will be too big to carry in a pocket and the antenna can protrude if the terminal is placed in a case and by that cause big trouble for the user when the terminal is not used. By the antenna being possible to fold into, or towards, the terminal, the mobile terminal will be more practical to carry since there is no protruding antenna.
• the antenna of one by hand carried mobile telecommunication terminal is influenced during operation by the user's head and hand. This influence means that a part of the to the antenna fed output power is lost as heating power in the user's head and hand.
• a reduction of said influence from the tissue of the user' s body consequently should increase the efficiency of the antenna.
• the invention relates to one at a mobile terminal arranged antenna element, which at use of said terminal makes possible a reduction of the from the antenna element transmitted high frequency radio waves towards the user' s head and hand. Said reduction results in that the attenuation of the radio waves are reduced, which in its turn results in that the range of the mobile terminal will increase without need to increase the transmission power.
• the invention is characterized in an antenna, preferably an antenna of type helix antenna, which is angled out from the mobile terminal at conversation state, and which at watching mode is arranged to be manually or automatically foldable towards, alternatively foldable into, the upper side of the terminal.
• An improved antenna efficiency results in an improved voice quality. If the antenna efficiency of the mobile terminal is improved, the battery consumption in transmission state will be reduced and the conversation time will be prolonged. Alternatively there is possibility to benefit from the improved antenna efficiency by providing the mobile terminal with a smaller and by that cheaper and lighter battery.
• An improved antenna efficiency of the mobile terminal means that it is possible for an operator to reduce the costs for network extension since the mobile terminal can be used under poorer communication conditions, for instance at larger distance from the opposite station. By that, distances between base stations in a mobile telecommunication network can be greater, which can result in a reduction of the investment in infrastructure for the mobile telecommunication network. In a cellular network the cells at that can be made larger.
• the mobile terminal With the antenna foldable into, or towards, the terminal, the mobile terminal will be more practical to carry, since there is no protruding antenna.
• Figure 1 shows the mobile terminal from the side with the antenna (1) in unfolded conversation state.
• Figure 2 shows the mobile terminal from the side with the antenna (1) in folded watching mode.
• Figure 3 shows the mobile terminal from above with the antenna (1) in folded watching mode.
• Figure 4 shows the mobile terminal from above with the antenna (1) in unfolded conversation state.
• Figure 5 shows the mobile terminal during call/conversation.
• Figure 6 shows the measurement environment with phantom hand (4) and phantom head (5) .
• Terminals which are used in telecommunication networks for mobile communication are equipped with antennas of different types.
• the antennas often are of a type which protrudes from the terminal, usually an extensible rod antenna or a fixed stub antenna.
• the from the antenna transmitted useful power is limited by losses in form of radiation which is attenuated by objects in the surroundings.
• the transmitted antenna power is especially influenced by very close, nearby objects - objects at a centimeter distance from the antenna element.
• the antenna is arranged according to the invention so that the radiation towards head and hand when the terminal is used held in hand against the head becomes smaller than it is at the today normal arrangement of antenna.
• an antenna (1) of type helix antenna or stub antenna is utilized, mounted on one short side of the terminal (6), see Figure 1-4.
• the antenna is mounted so that it can be angled out from the terminal in conversation state.
• the antenna should protrude at the back (8) of the terminal so that the angle between the antenna and the side of the user's head during use of the terminal for conversation is about 90°.
• the antenna can be located parallel with an above the short side (6) of the terminal, see Figure 2 and 3.
• the antenna arrangement according to the invention makes an antenna function primarily consisting of the stub antenna which protrudes from the terminal and articulated parts at the back (8) of the terminal.
• the radiation will be transmitted from parts of the terminal in connection with the back of the terminal.
• the transmitting parts by that will be at a relative great distance, several cm, form the user's head. By that, the losses caused by effects from the head will be limited so that a considerably better antenna efficiency is achieved.
• the antenna arrangement according to the invention has, compared with other solutions that are available, low losses and a neat design. Other antenna arrangements with corresponding efficiency are usually equipped with a big extensible/telescopic antenna.
• Measurement results from the use of the in this invention described antenna device have been compared with other measuring results from use of usually existing stub antennas.
• the measurements show that a reduction of "Body Loss" of 3-4dB is possible to achieve by an antenna design according to the invention.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Support Of Aerials (AREA)
• Telephone Set Structure (AREA)
• Telephone Function (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20418092

Family Applications (1)

Country Status (5)

Citations (6)

• 1999
  • 1999-12-13 SE SE9904541A patent/SE517911C2/sv not_active IP Right Cessation
• 2000
  • 2000-12-12 WO PCT/SE2000/002518 patent/WO2001043225A1/en active Application Filing
  • 2000-12-12 EE EEP200200320A patent/EE200200320A/xx unknown
  • 2000-12-12 EP EP00987895A patent/EP1250724A1/en not_active Withdrawn
• 2002
  • 2002-05-27 NO NO20022489A patent/NO326242B1/no not_active IP Right Cessation

Patent Citations (6)

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