Abstract: A wireless communication system base station uses a dual-polarized antenna array to receive two signal groups having orthogonal polarizations. In a preferred embodiment, a first signal group is received using a first sub-array of odd-numbered antenna elements, while a second signal group is received using a second sub-array of even-numbered antenna elements. Dipoles within the odd-numbered elements are selected so that they have a common polarization orthogonal to the dipoles selected in the even-numbered elements. The two signal groups thus have orthogonal polarizations. Base station signal processing hardware performs separate spatial channel estimation for these two groups, and uses the polarization diversity to improve performance in both the uplink and downlink. The use of polarization diversity allows the physical dimensions of the antenna array to be kept to a minimum.

Abstract: Embodiments of the present invention relate generally to receivers. One embodiment relates to a digital FM receiver having multiple sensors (e.g. antennas). In one embodiment, the digital receiver includes a baseband unit having a channel processing unit. In one embodiment, the channel processing unit is capable of calculating or estimating a phase difference between the incoming signals prior to combining them. One embodiment uses phase estimation method for diversity combining the signals while another embodiment utlizes a hybrid phase lock loop method. Also, some embodiments of the present invention provide for echo-cancelling after diversity combining. An alternate embodiment of the channel processing unit utilizes a space-time unit to diversity combine and provide echo cancelling for the incoming signals.

Abstract: An electronic device comprises first and second antennas for a first radio communication scheme that uses a diversity scheme, and a third antenna for a second radio communication scheme arranged between the first and second antennas.

Abstract: A wireless cellular communication system in which cellular base stations utilize multi-beam antenna to communicate with a large number of users. Each of the base station beams is a narrow beam of less than 10 degrees permitting reuse of available spectrum many times. A preferred antenna is described which broadcasts about 12 simultaneous beams, each about 5 degree, the 12 beams together covering a fan arc of about 60 degrees with the beams overlapping somewhat but interference is avoided by having adjacent beams broadcast at different frequencies within an authorized broadcast bandwidth. Six antennae mounted in a hexagonal manner thus cover a 360-degree azimuthal range. Preferably, users of the system communicate with the base station using a single narrow beam antenna directed at the base station.

Abstract: Systems and methods are described that provide global positioning system (GPS) enabled wireless communications. The wireless communications system provides a switching module that is adapted to couple communications circuitry to a first antenna or a second antenna as a function of communications characteristics of the first antenna or the second antenna. The switching module is also adapted to couple GPS circuitry to a first antenna or a second antenna as a function of GPS reception characteristics of the first antenna or the second antenna. The switching module may also provide the communications circuitry and the GPS circuitry with simultaneous access to different antennas.

Abstract: Method and apparatus for negotiating a transmission scenario in a mixed mode spectrum wireless communication system capable of both MISO and SISO traffic. The transmitter determines an antenna diversity configuration for a given communication link and applies a transmission scenario. The base station queries the remote station for antenna diversity status. In response to the antenna diversity status information, the base station determines and applies a transmission scenario. In one embodiment, a base station generates composite MIMO transmissions to multiple SISO mobile stations.

Abstract: At least one communication station is provided with a number of antennas having directivities, a communication station to which a radio signal is transmitted for the next communication is judged by the communication station provided with the number of antennas, an optimal antenna communicating with the communication station is judged based on a receiving state when a signal from the judged communication station was received in the past; and wireless communication is performed by using the judged antenna, so that when a network system is wirelessly composed of several stations, a quality of communication can be optimized.

Abstract: A portable telephone which includes a directional antenna is provided. The directional antenna is designed such that it can be positioned for use so that its beam is substantially parallel to the direction of received electromagnetic energy, thereby increasing the efficiency at which electromagnetic energy is transmitted to and received from the base station(s) as well as reducing the levels of electromagnetic energy transmitted into the body of the portable telephone user. In another embodiment, two directional antennas are provided for use with a diversity receiver and can be positioned for use to provide directional diversity, space diversity or both, thereby providing added immunity against fading.

Abstract: An antenna switch diversity algorithm, and systems and methods to provide antenna diversity by implementing the algorithm in, for example, an IEEE 802.11a compliant environment, are presented. In accordance with the algorithm, one antenna of at least two antennas is designated as a default antenna at a communications device that sends and receives transmit and receive packets. The default antenna designation is changed depending on long-term and short-term learning processes implemented in, for example, software and hardware. The long-term and short-term learning processes analyze packet transmission and reception results of the antennas. The antenna switch diversity algorithm is applicable to multiple antennas.

Abstract: A diversity antenna branch selection module includes first and second computation stages. The first computation stage computes an approximate bit error probability for each of K sub-carriers in an Orthogonal Frequency-Division Multiplexing (OFDM) signal for each of L different antenna branches n antenna branches at a time. The second computation stage processes the approximate bit error probabilities to identify a group of n of the L different antenna branches that minimizes an approximate bit error probability of a signal that will eventually be constructed from sub-carriers that are each received by any one of the n antenna branches in the identified group. The module is ideal for use in a system having n radio frequency receivers and for wireless local area network (WLAN) applications operating at high frequencies, such as 5 to 6 GHz, in multipath environments.

Abstract: Disclosed is a system and method providing beam forming and selection to provide desired signals to/from signal processing devices such as cell site modems. Systems of the present invention are operable with multi-beam antenna arrays to utilize antenna beams provided by the multi-beam antenna array and to form antenna beams which supplement the antenna beams formed by the multi-beam antenna array. Additionally, systems of the present invention are operable with adaptive array antennas to form antenna beams having desired characteristics. Preferably, predefined sets of beam forming weighting characteristics are utilized to provide a hybrid adaptive beam forming technique wherein antenna beams having predetermined characteristics may be rapidly selected and formed. Additionally, dynamically determined sets of beam forming weighting characteristics may be utilized to provide additional antenna beams having other desired characteristics.

Abstract: A method and apparatus for increasing the capacity of a multiple-input and/or multiple-output system. Each sub-stream of a primary data stream is stratified to produce a processed sub-stream whose strata can be separated out and decoded with an acceptable error rate. A sub-stream can be stratified by dividing it into a plurality of sub-stream-components that are processed to obtain strata, with each stratum representing one of the sub-stream-components. The strata are then combined to obtain the processed sub-stream. Stratifying allows a particular processed sub-stream's strata have different transmit features from each other, such as different bit rates, or different power levels, or both. This reduces the interference for some of the strata of each processed sub-stream since as stratum are separated out and decoded they are no longer interference for the other strata. Thus, allowing for a higher overall bit rate for the processed sub-streams.

Abstract: An antenna apparatus (200) including a forward link antenna array (212, 214, 216, 218) and a reverse link antenna array (210, 214, 220, 222) coupled by a plurality of circulators (224, 226, 228). The circulators direct the signals for the forward link and reverse link to and from the appropriate antenna elements in the appropriate direction. The forward link and reverse link antenna arrays use a common set of coaxial cables (230) to communicate with the base station circuitry.

Abstract: A first embodiment of the present invention is a method for displaying the quality of a wireless data transmission. The method involves receiving the wireless data transmission wherein the wireless data transmission comprises multiple streams of data, determining the quality of the wireless data transmission based on a quality parameter of the wireless data transmission and displaying the quality of the wireless data transmission. A second embodiment of the present invention includes an apparatus for indicating the quality of a wireless data transmission. The apparatus includes means for receiving the wireless data transmission wherein the wireless data transmission comprises multiple streams of data, means for determining the quality of the wireless data transmission based on a quality parameter of the wireless data transmission and means for displaying the quality of the wireless data transmission. A third embodiment of the present invention includes a wireless communication system.

Abstract: In a multiple-carrier modulation system, each carrier signal of the multiple carrier system is distributed, recombined, optionally band pass filtered, and transmitted to downlink devices such as cellular phones. The distribution and recombination is performed by either a space-fed technique or through the use of a Rotman lens fed in reverse. The phases of the distributed signals are controlled to be coherent when recombined. Also, a capacity of the multiple carrier system is enhanced through polarization of the carriers in a space-fed version of the system.

Abstract: The information terminal unit (3) comprises a transceiver (231) and a processor (232), while the variable directional antenna (1) comprises a main antenna element (201) to which the transceiver directly supplies a radio frequency signal, and a plurality of sub antenna elements (202 to 207). The sub antenna elements are connected with variable phase shifter circuits (212 to 217) for determining a phase shift amount of a reflecting wave, respectively. The control circuit (220) receives the directivity data from the CPU (232) of the information terminal unit (3) and analyzes the received data to control the phase shift amount of each variable phase shifter circuit (212 to 217) .

Abstract: A radio communication system comprises a communication channel between two terminals each comprising a plurality of antennas (108). The communication channel comprises a plurality of paths, and at least one of the terminals comprises a receiver having means (306, 308) for determining the directions from which the strongest signals are received, corresponding to paths between the terminals. The terminal may also include a transmitter having means (302) for separating a signal into a plurality of parts, each having a reduced bit rate, and transmitting the parts in respective directions corresponding to those from which the strongest signals are received.

Abstract: When there is a request of extracting a user signal transmitted through a control channel, the weight vector thereof is calculated and stored in a memory. When there is an extraction request of a user signal transmitted through a conversation channel, the weight vector thereof is calculated using the stored weight vector as an initial value. Thus, the calculation time required for the weight vector to converge can be reduced.

Abstract: A method provides for an improved compensation Fourier channel characteristics in a wireless communication embodiment. The method identifies one or more information carriers as pseudo pilot tones whose information may be realized to enhance the determination of the complex coefficient of the communication channel.

Abstract: A distributed antenna array comprising a plurality of antenna elements, and a plurality of power amplifiers, each power amplifier being operatively coupled with one of said antenna elements and mounted closely adjacent to the associated antenna element, such that no appreciable power loss occurs between the power amplifier and the associated antenna element, each said power amplifier comprising a relatively low power, linear power amplifier.

Abstract: The present invention describes an inexpensive as well as efficient smart antenna processor for a code division multiple access (CDMA) wireless communications system, such as a 3rd generation (3G) CDMA2000 or W-CDMA system. Separate channel estimation is not required in the present invention, in contrast to a CDMA system with a conventional smart antenna. In addition, the phase distortions due to the different radio frequency (RF) mixers can be automatically compensated in the present invention. Thus, separate phase calibration is not necessary for a smart antenna processor according to the present invention, if the reverse link demodulation is concerned. Furthermore, bit error rate (BER) performance of a CDMA system with the adaptive algorithm in the present invention can be smaller than that of a conventional algorithm, for fading and additive white Gaussian noise (AWGN) environments.

Abstract: Antenna systems for electronic devices, such as radiotelephones, include a paging antenna that enhances paging mode operation when a pivotable primary antenna is in a stored position. Paging antennas are disposed within a hinge rotatably secured to one end of a radiotelephone housing. A primary antenna, in electrical communication with the transceiver, is secured to the hinge and rotatable therewith along a predetermined path of rotation from a stored position adjacent the housing to an operating position extending away from the housing. Radiation axes for a primary antenna and a paging antenna are orthogonal.

Abstract: A method and apparatus for selecting an optimal set of antennas from a plurality of antennas for use by a transmitter and/or receiver having a plurality of RF chains to transmit and/or receive a wireless signal on a wireless link. According to the invention information concerning transmission of wireless signals on the wireless link is determined and an optimal set of antennas from the plurality of antennas is selected based on the information. Thereafter, the RF chains are connected to the optimal set of antennas to permit transmission and/or reception of the wireless signal from the RF chains on the wireless link via the optimal set of antennas. The RF chains correspond in number to the number of antennas in the optimal set of antennas, and the number of antennas included in the plurality of antennas is greater than the number of RF chains.

Abstract: A method and apparatus for receiving an incident signal using a phased array antenna (1). Embodiments are provided that demonstrate the acquisition, tracking and reception of frequency modulated video signals (63) transmitted by a mobile television radio-camera in a multipath environment.

Abstract: A cellular radiotelephone base station communicates with cellular radiotelephones by receiving cellular radiotelephone communications energy from cellular radiotelephones on an antenna array, processing the received communications energy to produce at least three processed radiotelephone communications signals representing communications energy received from a coverage sector, and selecting at least two of the processed signals for decoding in a conventional decoder. Preferably, the selected signals are the processed signals having the highest power or signal quality.

Abstract: A change in a time derivative of a branch's received power is determined. In response to the absolute value of the received power exceeding a predetermined threshold, a second branch is switched to. The determination of the rate of change of the received power can include use of a received-signal-strength indicator. The threshold can be a function of modulation and coding. A rapid change in the time derivative of the received power indicates that the branch will soon become frequency selective and that, therefore, the second branch should be switched to in order to avoid the negative affects of the frequency selectivity of the first branch.

Abstract: Wireless communication systems and methods using multiple overlapping sectored cells. Two or more cells in which communication services are provided to a number of subscriber stations at least partially overlap in an overlapping region and are each divided into a number of sectors. A first cell uses a first group of channels to communicate with at least some subscriber stations that are located in the first cell, and a second cell uses a second group of channels to communicate with at least some subscriber stations that are located in the second cell. The sectored cells use different communication channels in respective overlapping sectors of the overlapping region. In this manner, one or more first cells may be deployed with one or more second cells either initially or in a modular fashion over time to flexibly accommodate various topological distributions of subscriber stations and varying capacity demands in a wireless communication system without posing significant interference problems.

Abstract: The present invention relates to a base station of a radio system whose antenna means (11) include: means (6 to 8) for receiving signals associated with the same logical channel by at least two antenna beams (1 to 4), measuring means (8) for measuring the signal level of the signals received by the antenna beams, and control means (8) for selecting one or more antenna beams (1 to 4) and for supplying the signals of the selected antenna beam to a receiver unit (5) of the base station (BTS1). In order that the best possible signal would be definitely transmitted to the base station, the base station (BTS1) comprises means for measuring the quality of the signals and for generating a quality signal (BER) and for supplying it to the control means (8), and the control means (8) are arranged to select an antenna beam (1 to 4) on the basis of the signal level measured by the measuring means and the quality signal (BER) supplied to the control means.

Abstract: Antenna systems are used for transmitting common overhead channels (pilot, sync, and paging channels) over a whole sector while transmitting and receiving unique traffic channels on individual beams in the sector. Each beam in the sector is transmitted at a frequency offset from other beams in the sector. The offset frequency is chosen such that the effect of cancellation of the pilot channel caused by the summing of signals from multiple beams is minimized. Alternative, each beam in the sector can have a time dependent phase offset relative to each other to minimize the effect of cancellation of the pilot channel caused by the summing of signals from multiple beams. System capacity is substantially increased since the number of traffic carrying beams per sector is increased without using more pilot channel PN offsets. Beams are fixed and the same antennas are used for the overhead channels as the traffic channels, obviating the need for complex algorithms and calibration procedures.

Abstract: A receiver that uses multiple antennas to receive signals arriving over multiple paths and is configured for enhanced received signal path detection accuracy and improved reception quality includes receive weight generating means that generates receive weights for every antenna based on signals received from the antennas, summing means that calculates sums of results obtained by multiplying the signals from the antennas and the receive weights of the individual antennas generated by the receive weight generating means, and path detection means that detects the paths of the received signals based on the sums calculated by the summing means.

Abstract: A concentrator (11) coupled to a wired network (13) also acts as a master device relative to each of a plurality of ad hoc wireless communication networks (15), thereby permitting wireless communication devices in the ad hoc networks to access the wired network. The concentrator utilizes antenna array processing and beamforming techniques when communicating with the devices of the various networks, in order to advantageously reduce communication interference between the networks.

Abstract: A receiver device for receiving incoming radio waves by using a plurality of antennas, which is capable of improving the maximum input sensitivity is provided. In the receiver device, a switching unit switches to an antenna having the lower antenna gain as a new receiving antenna on the precondition that when receiving incoming radio waves by one particular antenna currently set as the receiving antenna, if a reception level of this particular antenna becomes a level close to the maximum input sensitivity of a signal processing unit, then the reception condition is satisfactory. Consequently, it is possible to improve the maximum input sensitivity and forestall the occurrence of waveform distortion and the like.

Abstract: An antenna module for a cellular phone which is capable of minimizing the effect of electromagnetic radiation of the cellular phone on the human body and enhancing the quality of speech of the cellular phone. The antenna module comprises two helix antennas installed in the cellular phone transversally apart from each other, and a power supply unit connected to the helix antennas for applying two power signals with the same power level and opposite phases respectively to the helix antennas. This antenna module is able to radiate a minimized amount of electromagnetic waves in the longitudinal direction of the cellular phone, or toward either the top or rear part of the cellular phone, and an increased amount of electromagnetic waves in the transversal direction of the cellular phone, respectively, thereby minimizing electromagnetic radiation to the human body while at the same time enhancing the quality of speech of the cellular phone.

Abstract: A dual band radio telephone with separate dual band, dual feed point transmit and receive antennas. The dual band radio telephone has two transceivers. Two feed points of the dual band, dual feed point receive antenna are coupled to respective receive branches of the two transceivers. Two feed points of the dual band, dual feed point transmit antenna are coupled to respective transmit branches of the two transceivers. Additionally, image reject band pass filters are coupled between the feed points of the dual band, dual feed point receive antenna and the respective receive branches. When the dual band, dual feed point transmit and receive antennas are spaced apart closely, the transmit branches comprise transmit filters coupled between transmit power amplifiers and the two feed points of the dual band transmit antenna.

Abstract: A method provides a technique for optimally combining communication beams. The method forms a plurality of beams from captured signals. One beam is selected as the primary beam while a subset of the others are applied to auxiliary receivers. A digital signal processor weights and combines these primary and secondary beams.

Abstract: An adaptive antenna reception apparatus includes a reference signal level determination section, reception level detection sections, and beam formers. The reference signal level determination section determines the level of a reference signal for generating an error signal used for antenna adaptive control on the basis of a reception level of each antenna before beam forming. The reception level detection sections calculate antenna weighting factors for the respective paths on the basis of the multiplex signals received through the respective antennas and the error signal output from the reference signal level determination section. The beam formers receive the received multiplex signals and form antenna directivity beams for the respective paths in accordance with the antenna weighting factors output from the reception level detection sections.

Abstract: A radio apparatus includes a plurality of receiving systems connected to multiple antennas providing diversity, respectively, each receiving system including an antenna terminator and a preamplifier. After one receiving system is discriminated from another receiving system based on radio signals received by the receiving systems, respectively, a controller controls the one receiving system such that an antenna terminator is inactive and a preamplifier is active and, at the same time, further controls the other receiving system such that an antenna terminator is active and a preamplifier is inactive.

Abstract: In a system for sending wireless communication signals on at least one downlink wavelength and receiving wireless communication signals on at least one uplink wavelength, there is a ratio r equal to the larger divided by the smaller of these wavelengths. The system comprises a receiver operative to receive signals imposed on a carrier having the uplink wavelength, a transmitter operative to transmit signals imposed on a carrier having the downlink wavelength, and an array of independent antenna elements. The array comprises a first and a second sub-array. One sub-array is electrically coupled to the transmitter, such that transmitted signals can be radiated from it, and the other sub-array is electrically coupled to the receiver, such that signals to be received can be extracted from it. The sub-arrays are geometrically similar to each other with a relative scale factor equal to the wavelength ratio r. The sub-arrays have at least one common antenna element.

Abstract: An integrated circuit including a structure of inductances on a semiconductor substrate, intended for operating at frequencies greater than several hundreds of MHz, including a first inductance formed by a conductive track and having first and second terminals respectively connected to each of the two ends of the conductive track, including a second inductance formed by the conductive track between the second terminal and any intermediary point of the conductive track connected to a third terminal, said second and third terminals forming the two terminals of the second inductance, and means for setting the third terminal to high impedance when the first inductance is used.

Abstract: An antenna diversity receiver is disclosed. The antenna diversity receiver includes an antenna selective switching means for coupling one of a plurality of antennas to a RF receiver input. A multipath detector controls the antenna selective switching means. A switching disabling means automatically disables the antenna selective switching means over a disabling period. In order to accurately immunize the receiver the disabling period is controlled by an adjacent channel detector to increase the period with increasing adjacent channel interferences and vice versa.

Abstract: An array antenna transceiver includes an antenna section, N transceiver blocks, a common reference signal generating section and a transceiver control section. The antenna section has antenna elements. The N transceiver blocks are connected to the antenna elements. Each of the N transceiver blocks generates an individual reference signal. The transceiver block carries out transmission of a transmission signal and reception of a reception signal based on an common reference signal using a corresponding antenna element as a part of an array antenna in an array mode and based on said individual reference signal using the corresponding antenna element as an individual antenna element in an individual mode. The common reference signal generating section supplies the common reference signal to the N transceiver blocks. The transceiver control section sets said array mode when said common reference signal is used, and said individual mode when said individual reference signal is used.

Abstract: The present invention provides a method for controlling a communication parameter in a channel through which data is transmitted between a transmit unit with M transmit antennas and a receive unit with N receive antennas by selecting from among proposed mapping schemes an applied mapping scheme according to which the data is converted into symbols and assigned to transmit signals TSp, p=1 . . . M, which are transmitted from the M transmit antennas. The selection of the mapping scheme is based on a metric; in one embodiment the metric is a minimum Euclidean distance dmin,rx of the symbols when received, in another embodiment the metric is a probability of error P(e) in the symbol when received. The method can be employed in communication systems using multi-antenna transmit and receive units of various types including wireless systems, e.g., cellular communication systems, using multiple access techniques such as TDMA, FDMA, CDMA and OFDMA.

Abstract: A low-cost diversity antenna switching system and method is realized by controlling bias voltages on PIN diodes. By increasing the reverse bias voltage impressed upon a PIN diode, an RF signal impressed upon the diode is increasingly attenuated. As the PIN diode is forward biased to conduct in the forward direction, RF attenuation decreases. Two or more PIN diodes are used to increasingly attenuate signals from one antenna as attenuation of signals from another antenna is gradually decreased. The progression of the bias voltages is accomplished using a microprocessor that monitors a received signal strength indicator (RSSI) signal from a radio receiver. The RSSI is used to control which of two antennas are coupled into the receiver by predicting a signal fade.

Abstract: A personal communications terminal includes a telephone unit and an application processing unit that are operatively connected. The telephone unit includes a first RF transceiver for communicating with a cellular communications network via an external dipole antenna. The application processing unit includes a short range transceiver and antenna for connecting the computing device with an external computer or local area network. The short range antenna is a slot antenna formed by a slot in the housing of the personal communications terminal.

Abstract: A radiocommunication system is described wherein a flexible transceiver is provided that can be switchably connected to different antenna structures. Switching matrices are provided between the antenna elements and the receive processing circuitry which, under the control of the central processing unit, allows the transceiver to handle the different antenna structures. The enhanced flexibility achieved by the present invention provides a novel transceiver which can, for example, be reconfigured between and during calls to dynamically assign resources based upon changes in the amount and type of load being experienced by the system and adjusted in order to render existing operating functions more efficient.

Abstract: A diversity receiver includes a plurality of antennas, a receiving unit for receiving radio waves via the antennas, a phase adjuster disposed for each said antenna and connected thereto for adjusting a phase angle of a radio wave received by each of the antennas to a value to increase gain of each antenna to which the phase adjuster is not connected, and a switching unit, operative in response to a control signal indicating a selected antenna having a best reception state to receive an external radio wave, for connecting the selected antenna to the receiving unit, for disconnecting the selected antenna from the phase adjuster and non-selected antennas other than the selected antenna, and for connecting the non-selected antennas to the phase adjuster associated therewith. The phase adjuster is connected in a stage subsequent to the switching unit viewed from the antennas. This configuration provides a highly efficient diversity receiver.

Abstract: A system and method for generating a coherent reference signal for extracting desired user signals from received signals even after error propagation is underway, are presented. A data symbol preceding a sequence whose relative phases are known is used as an absolute phase reference. Since errors in detection of the phase reference symbol are usually caused by error propagation already underway, the sequence can be used to reacquire the desired signal with merely an absolute phase shift in detected data, which allows accurate differential detection of the desired user signal even in the absence of absolute phase knowledge.

Abstract: A radio base station, upon receipt of a traffic channel assignment request from a mobile station, creates a piece of traffic channel assignment information, attaches a diversity reception stop instruction to the information, and transmits the information with the diversity reception stop instruction to the mobile station as a response to the traffic channel assignment request.

Abstract: Antenna systems for electronic devices, such as radiotelephones, include a paging antenna that enhances paging mode operation when a pivotable primary antenna is in a stored position. Paging antennas are disposed within a hinge rotatably secured to one end of a radiotelephone housing. A primary antenna, in electrical communication with the transceiver, is secured to the hinge and rotatable therewith along a predetermined path of rotation from a stored position adjacent the housing to an operating position extending away from the housing. Radiation axes for a primary antenna and a paging antenna are orthogonal.

Abstract: Corresponding to transmission data 101, phase controller 105 is controlled to shift a phase of modulated signal 103 by 0° or 180°. Planes of polarization of modulated signals to be transmitted from antennas 106 and 107 are made different from each other corresponding to transmission data 101. The electric field strength of a signal received at antenna 108 changes corresponding to the plane of polarization, thereby voltage value 113 output from electric field strength detector 111 varies corresponding to transmission data 101, and using this variation, judged result 115 is obtained. Two results, namely, demodulated data 112 and judged result 115 are input to comparing circuit 116, whereby the reception apparatus is capable of obtaining received data 117 with high quality.