Abstract: A multi-carrier linear equalization receiver, e.g., a RAKE receiver or chip equalization receiver, is described herein. The multi-carrier receiver distributes processing delays among a plurality of received carriers based on a comparison between the signal-to-interference ratios (SIRs) determined for each carrier. The receiver initially allocates a minimum number of processing delays to each carrier. In one embodiment, any remaining additional processing delays are distributed evenly between the carriers when a comparison between the largest and smallest SIR is less than or equal to a threshold. In another embodiment, the remaining additional processing delays are distributed to favor the carrier(s) with the strongest SIR(s) when the comparison between the largest and smallest SIR exceeds the threshold.

Abstract: An apparatus and a method for transmitting a Coexistence Beacon Protocol (CBP) packet in a Cognitive Radio (CR) wireless communication system are provided. In the method for transmitting CBP packet in a transmitter that operates in a scalable Orthogonal Frequency Division Multiple Access (OFDMA) mode, a priority is given to each channel of one or more channels based at least partly upon channel use statuses of two or more neighbor Wireless Regional Area Networks (WRANs). Whether a Quality of Service (QoS) for CBP packet transmission for each channel is met is sequentially determined according to the respective priority. A channel having a highest priority is selected from the one or more channels meeting the QoS as a channel for CBP packet transmission. A CBP packet is transmitted via the selected channel.

Abstract: Synchronization tracking in an orthogonal frequency division multiplexing (OFDM) receiver by obtaining a DFT output vector; determining a sample timing offset indication using reference symbols extracted from the DFT output vector; and adapting the OFDM symbol timing using said determined indication. To provide an improved post-DFT algorithm for estimating time tracking error in OFDM receivers the determining includes (a) estimating the channel transfer function at equidistant frequency positions using said reference symbols, for a first OFDM symbol; determining plural frequency correlations for said equidistant frequency positions for said OFDM symbol; (c) repeating steps (a) and (b) for subsequent OFDM symbols; (d) linearly combining said plural frequency correlations for said plural OFDM symbols obtained in steps (a) through (c), for obtaining said sampling clock offset indication wherein the linear combining uses nonzero weights only. An OFDM receiver circuit arrangement performing this method.

Abstract: A carrier frequency offset between a base station and a receiver of an Orthogonal Frequency Division Multiplex communication system is estimated by maximizing a function depending on the carrier frequency offset. The function is built using a sequence received by the transmitter when the base station emits a pilot sequence, taking into consideration a variance of the noise and a presumed length of the channel.

Abstract: A method of transmitting a control channel format indicator (CCFI), also known as PCFICH (Physical Control Format Indicator Channel), in case where the length of a coded CCFI is not an integer multiple of three, including mapping a plurality of two-bit CCFI into a codebook with each component codeword having three bits; generating a sequence of codewords selected from the codebook by repeating the selected component codeword for predetermined times; generating a codeword by concatenating the sequence of the selected component codewords with the original CCFI bits; and transmitting the codeword carrying information of CCFI. The method further includes a step of generating a permutation of each of the four codewords by assigning K repetitions of the three-bit component codeword to the number of K resource units respectively and mapping remaining K bits of each of the four codewords separately to the number of K resource units.

Abstract: The present disclosure presents a predictive signal producing method that effectively levels transmitter output power in a multi-carrier communication system and results in approaching amplifier performance normally associated with constant carrier waveforms. Embodiments of the disclosed solution offers >10 dB reduction in the peak-to-average power required to support the transmission of, for example, orthogonal frequency division modulation (“OFDM”) modulation techniques. Embodiments of the novel system and method maximize peak-to-average power ratio (“PAPR”) reduction with selective mapping and soft clipping, which may include filtering, combined. This novel approach also minimizes overhead, bit error rate, retransmissions, and increases latency as well as implementing processing cycles with a number of iterations.

Abstract: A method select a codebook for transmit beamforming. The method constructs an estimated channel matrix based on a codebook, selects a channel submatrix from the estimated channel matrix, calculates a selection matrix from the channel submatrix; and assigns a steering matrix based on the selection matrix. There may be multiple codebooks and the method may construct an estimated channel matrix, select a channel submatrix, and calculate a selection matrix for each of the codebooks, then select an optimal codebook. The steering matrix is assigned based on the optimal codebook. The steering matrix may be used in steering a transmitted packet. The method may also calculate a post-MIMO equalizer signal-to-noise ratio for a data stream, based on the estimated channel matrix and the selected codebook. A related system is also disclosed. Other embodiments are provided, and each of the embodiments described herein can be used alone or in combination with one another.

Abstract: Apparatuses and methods for transmitting and receiving in a multi-antenna system are provided. A receiver for reducing a quantization error of channel information feedback in a multi-antenna system includes a restore vector generator for selecting a codeword ck and d determining a real part wkreal and an imaginary part wkimag of a restore vector corresponding to the codeword; and a post-processor for performing post-processing by multiplying the real part wkreal of the restore vector by a first reception signal and multiplying the imaginary part wkimag of the restore vector by a second reception signal.

Abstract: Provided herein is a method of designing a network codebook that may be shared by a plurality of base stations. Also provided herein is a feedback method of a terminal using the network codebook. The network codebook design method may design the network codebook by processing a pre-defined first codebook based on large scale fading of the base stations. The terminal may more effectively feed back a preferred matrix indicator with respect to the network codebook.

Abstract: A method for processing a preamble of a data unit transmitted via a communication channel includes receiving a signal via a plurality of antennas, applying a plurality of distinct steering vectors to the received signal to generate a plurality of respective outputs, and using the plurality of outputs to perform at least one of carrier sensing and symbol timing synchronization associated with the preamble.

Abstract: A method and system for beamforming signal transmission under a per-antenna power constraint is presented. In one aspect, a multiple input multiple output (MIMO) transmitting station may compute a per-antenna power gain factor for each of a plurality of transmit chain signals. The transmit chain signals may be concurrently transmitted by a plurality of transmitting antennas at the MIMO transmitting station. The plurality of transmit chain signals may correspond to beamforming signals, which are generated by performing spatial mapping on a plurality of space-time signals. The plurality of power gain factors may be computed based on a per-antenna power constraint. Alternatively, the plurality of power gain factors may be computed based on joint per-antenna power and total-power constraints. Each of the transmit chain signals may be amplified or attenuated based on the corresponding antenna gain factor. The amplified or attenuated signal is then transmitted by the corresponding transmitting antenna.

Abstract: The present invention provides feedback control information for the multiple base stations multiple input multiple output (MIMO). The feedback control information according to the present invention includes a target resource unit (TRU) indicating a frequency resource unit to be measured for a feedback. A mobile station according to the present invention transmits feedback information worked on the latest best subbands reported for single base station MIMO.

Abstract: A method includes receiving from a first station at a second station at least two space-time coded signals in respective formed beams of a multi-beam antenna array associated with the first station; receiving from the first station, in a signaling channel, a value representing a transmit power level; determining power control coefficients for each of the space-time coded signals; and transmitting the power control coefficients to the first station, wherein the control coefficients are for in part adjusting transmit power.

Abstract: A transmitting terminal includes a signal processing unit, MS RF units, MT transmit antennas and a switch unit. The signal processing unit has K precoders for precoding K data streams corresponding to K receiving terminals. The MS RF units output MS up-converted transmit signals based on the precoded K data streams. The switch unit is coupled between the RF units and the transmit antennas and controlled by the signal processing unit for selection of the transmit antennas. The signal processing unit sets the MT transmit antennas as a universal set, calculates a plurality of sum rates corresponding to a plurality of subsets, each subset excluding an ith transmit antenna, according to channel state information, selects the subset with a maximum sum rate as the universal set of a next iteration, and then repeats the calculating and selecting steps until the subset with the maximum sum rate remaining MS transmit antennas.

Abstract: Apparatus and methods for use in a wireless communication system are disclosed for reducing channel estimation noise in a device such as a wireless transceiver. A disclosed apparatus includes a processor that determines a channel activity portion and a noise portion of a channel estimation. The processor also determines a threshold noise level based on channel estimate values in the noise portion of the channel estimation. The processor compares channel estimate energy values in the channel estimation to the threshold noise level and sets each of the channel estimate energy values being less than the threshold noise level to a predetermined value such as zero in order to reduce or eliminate the noise. Similar methods are also disclosed.

Abstract: A local carrier wave output from a synthesizer to quadrature demodulators is multiplied by an offset that makes a frequency shift by an integer number of subcarriers in units of sub-carrier bands. The offset is set to a value obtained by multiplying the number sequentially counted up from 0 to the number of unused sub-carriers included in guard tones in a signal band by the bandwidth of a sub-carrier. By shifting the frequency of the local carrier wave at the time of quadrature demodulation with the offset, the SNR of a baseband signal is prevented from being constantly degraded by a frequency characteristic possessed by the circuit of a receiver in a particular sub-carrier signal. Especially, by preventing a pilot signal from being constantly degraded, the signal can be received with higher accuracy.

Abstract: A method codes data in a transmitted signal. The transmitted signal comprises multiple subcarriers with orthogonal frequencies. The signals are modulated corresponding to a given subset of the subcarriers of the transmitted signal in order to encode information. The signal is modulated corresponding to least one reserved subcarrier depending on at least one optimization criterion relating to a quality of the overall transmitted signal. In order to enhance the quality of the transmitted signal, the optimization criterion depends on at least one first quantity relating to a peak-to-average-power ratio of the transmitted signal and on at least one second quantity relating to an out-of-band power of the transmitted signal.

Abstract: Following a transmission comprising a plurality of symbols, an error measurement is generated for each symbol, so that one may distinguish between symbols having a relatively low error and symbols having a relatively high error. A bit rate to be used for subsequent transmission is determined as a function of error measurements of those symbols that have relatively low error and as a function also of the proportion of symbols having a relatively high error, such that the bit rate reduces as the proportion increases. Measurement of the error rate and/or the durations of high and low error conditions may also be used to set other transmission parameters such as error-correcting code and interleaver settings.

Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.

Abstract: A method and an apparatus for transmitting a reference signal in a multiple antenna system are provided. The method includes transmitting a common reference signal through N antennas (N<M, where M and N is a natural number), and transmitting a dedicated reference signal through M?N antennas, wherein the common reference signal is transmitted to all user equipments within a cell, and the dedicated reference signal is transmitted to at least one user equipment within the cell.

Abstract: A space-time signal processing system with advantageously reduced complexity. The system may take advantage of multiple transmitter antenna elements and/or multiple receiver antenna elements, or multiple polarizations of a single transmitter antenna element and/or single receiver antenna element. The system is not restricted to wireless contexts and may exploit any channel having multiple inputs or multiple outputs and certain other characteristics. Multi-path effects in a transmission medium cause a multiplicative increase in capacity.

Abstract: A transmission circuit (100) according to the present invention includes an RF-IC (110), an EM-IC (120), and a power amplifier (130). The EM-IC (120) includes a DC-DC converter (123), a transistor (124), a low-dropout regulator (121), and a regulator output selector switch (122). After an elapse of a predetermined time from a time when an operation mode of the transmission circuit has switched from a polar modulation mode to a quadrature modulation mode to a time when a power supply voltage for the quadrature modulation mode output from the DC-DC converter (123) stabilizes at a desired value, the regulator output selector switch (122) switches a connection destination of a gate of the transistor (124) to a fixed potential, and outputs as a control voltage the power supply voltage for the quadrature modulation mode output from the DC-DC converter (123).

Abstract: A communication receiver which applies signal processing for quantitatively estimating receive signal factors such as communication channel quality, signal characteristics, and overall system received bit error rate (BER) or packet error rate (PER) and which applies a general algorithm for mapping these estimated factors to control receiver performance and minimize power consumption.

Abstract: A procedure for compensating the DC component inherent in any radio frequency chain making it possible from a single measurement, generally located in the digital stage, to determine a set of multiple compensation values that must be applied to multiple compensation points of the analogue chain. The compensation values are calculated by an iterative process converging towards a cancellation of the DC component and avoid saturating amplification components and components of the analogue digital converter.

Abstract: A method and apparatus for aligning I- and Q-signals in a quadrature receiver based on an squared signal. A correction is evaluated in an iterative manner by finding an average of the squared signal. The average squared signal may be the received signal, in which case the iterations are applied in a feed forward manner. Alternatively, the average squared signal is the aligned signal in which case the iterations are applied in a feed back manner. The correction may include the evaluation of an normalization or, in the feed back case, this can be implicitly included in the manner in which the iteration is applied. Various parameters to the iteration can be set to accommodate the operating environment of the receiver and characteristics of the received signal.

Abstract: A wireless apparatus includes: an A/D converter which samples an in-phase signal component and a quadrature signal component from a quadrature-modulated signal of analog form alternately; a digital quadrature demodulation unit which applies digital quadrature demodulation to an output signal of the A/D converter and outputs an in-phase signal and a quadrature signal; and an error detection unit which, based on the in-phase and quadrature signals output from the digital quadrature demodulation unit, detects a time difference error between the sample timing of the in-phase signal component and the sample timing of the quadrature signal component.

Abstract: In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.

Abstract: According to an example embodiment, a communications receiver may include a variable gain amplifier (VGA) configured to amplify received signals, a VGA controller configured to control the VGA, a plurality of analog to digital converter (ADC) circuits coupled to an output of the VGA, wherein the plurality of ADC circuits are operational when the communications receiver is configured to process signals of a first communications protocol, and wherein only a subset of the ADC circuits are operational when the communications receiver is configured to process signals of a second communications protocol.

Abstract: Time filtering channel estimates in a wireless communication system, such as an Orthogonal Frequency Division Multiplex (OFDM) system, can be used to improve the quality of channel estimates. The characteristics of an optimal channel estimate time filter can depend on the manner in which the channel estimate is determined as well as the time correlation of channel estimates. A receiver can implement an adaptive time filter for channel estimates in which the time filter response can vary based on channel estimate parameters. The channel estimate parameters can include the manner of determining channel estimates, a time correlation of channel estimates, and an estimated Doppler frequency. The time filter response can be varied continuously over a range of responses or can be varied discretely over a predetermined number of time filter responses.

Abstract: A low complexity system and method for operating a receiver in order to estimate an offset between the actual sample clock rate 1/TS? of a receiver and an intended sample clock rate 1/TS. The receiver captures samples of a received baseband signal at the rate 1/TS?, operates on the captured samples to generate an estimate for the clock rate offset, and fractionally resamples the captured samples using the clock rate offset. The resampled data represents an estimate of baseband symbols transmitted by the transmitter. The action of operating on the captured samples involves computing an error vector signal and then estimating the clock rate offset using the error vector signal. The error vector signal may be computed in different ways depending on whether or not carrier frequency offset and carrier phase offset are assumed to be present in the received baseband signal.

Abstract: A method for QR-maximum likelihood detection (QR-MLD) demodulation is provided. The method includes determining a transmission reception mode, receiving symbols represented by a received symbol vector, generating a channel matrix, and performing QR decomposition on the channel matrix to compute a unitary matrix and an upper triangular matrix. The method further includes the steps of processing the received symbol vector by multiplying the received symbol vector by the Hermitian of the unitary matrix, determining whether a conjugate calculation will be required to set a conjugate flag, computing a first distance metric by performing a conjugate or non-conjugate first distance metric calculation depending on the conjugate flag, and computing an estimated symbol by performing a conjugate or non-conjugate estimated symbol calculation depending on the conjugate flag.

Abstract: Two decoding algorithms are introduced for the decoding of multi-level coded modulation and other types of coded modulation involving component codes and interleaving operations. An improved hard iterative decoding (IHID) algorithm is presented that improves upon a hard iteration decoding technique by adding a stopping criterion. Also, a list Viterbi hard iteration decoding (LV-IHID) algorithm is presented that employs list decoding in conjunction with the IHID algorithm. Both of these decoding algorithms improve upon conventional multi-stage decoding by reducing the effective error multiplicity that is observed at the lowest coding level. It is demonstrated that the LV-IHID algorithm performs close to soft iterative decoding. The computational and delay complexity of the proposed decoding algorithms compare favorably with soft iterative decoding strategies. Also, a novel labeling strategy for MLC design is presented.

Abstract: Apparatus for determining a location of a peak in correlation output samples, the apparatus being arranged to receive samples from at least one correlator over a plurality of symbol time periods; combine samples from a period that is longer than the symbol time period into combined samples; and determine the position of a peak in the combined samples.

Abstract: A method and apparatus for estimating a Doppler frequency in a mobile terminal are provided. The method includes calculating two autocorrelation values for intervals of at least one sample from a channel estimation tap with a maximum power, and estimating a maximum Doppler frequency using the two autocorrelation values. The two autocorrelation values are autocorrelation values for intervals of different numbers of samples.

Abstract: A system including a control module and a correlation module. The control module partitions a total number of subcarriers, in a received signal, into a predetermined number of bands. The correlation module generates a plurality of correlation values for a plurality of preamble sequences. A correlation value for a preamble sequence is generated by correlating symbols in each band with corresponding symbols in the preamble sequence to generate correlations for each band, adding the correlations generated for a respective band to generate a sum for each band, and adding the sums generated for all the bands. The control module select a largest correlation value from the plurality of correlation values and determine that one of the preamble sequences is detected in the received signal in response to the largest correlation value being greater than or equal to a predetermined threshold.

Abstract: A multistage channel estimation method and apparatus is provided. The multistage channel estimation method includes: receiving a data frame to compensate for a distortion of the data frame based on a first channel estimation value associated with a corresponding section of the data frame; a first step of changing the corresponding section to calculate a second channel estimation value associated with the changed section; a second step of updating the first channel estimation value based on the calculated second channel estimation value; a third step of compensating for the distortion of the data frame based on the updated first channel estimation value to count a number of compensations; and repeating the first step through the third step, when the counted number of compensations does not match a predetermined numerical value.

Abstract: Example embodiments include methods of interference cancellation at NodeB receivers of baseband antenna signals including physical channels. The methods include canceling interference from a received baseband antenna signal by removing a reconstructed baseband signal from the processed received baseband antenna signal. The processed reconstructed baseband signal includes users whose physical data channel signals were successfully decoded. Methods also include removing interference from a received baseband signal to form an interference cancelled baseband signal that will be processed by the receiver. The interference cancelled baseband signal is the received baseband antenna signal minus users' signal interference contributions whose demodulated physical data channel signals have a determined user symbol energy value that exceeds a threshold. Methods further include removing interference from a user's signal to be error corrected.

Abstract: An SIR estimate of a communication signal in a wireless communication system receiver is calculated based on soft bit values output by a nonlinear detector. The average amplitude of the detector output soft bits is estimated. The average power of the detector output soft bits is estimated, e.g., as a mean-square or variance. An SIR of the communication signal is estimated based on the soft bit amplitude and power estimates. In particular, the SIR is estimated as the ratio of the square of soft bit amplitude to the difference between the mean square soft bit power and the square of soft bit amplitude, or the ratio of the square of soft bit amplitude to the variance. In either case, the SIR estimate may be scaled to obtain the desired units. The communication signal may be a received signal, or a simulated signal generated using channel estimates obtained from, e.g., a pilot channel.

Abstract: A method is provided for equalizing OFDM symbol vectors received on AM in-band on-channel radio signal including a main carrier and first and second BPSK modulated subcarriers. The method comprises the steps of: computing a BPSK magnitude signal; filtering the BPSK magnitude signal; filtering complex samples received on the main carrier; using the filtered BPSK magnitude signal and the filtered complex samples received on the main carrier to compute a plurality of flat fade equalization coefficients; and multiplying the OFDM symbol vectors by the flat fade equalization coefficients. A receiver that includes an equalizer, which operates in accordance with the method is also provided.

Abstract: Embodiments of the present invention provide systems, devices and methods for modeling and correcting amplitude and quadrature phase errors generated within analog components of a receiver. A frequency-dependent correction method is employed that closely tracks the frequency dependent nature of the mismatch between the I and Q polyphase filter responses. In particular, digital correction is performed on a signal based on a modeled error function generated during a calibration of the receiver.

Abstract: The present invention provides a communications system, node and method of operation for forming a wireless network from independently operating nodes that have the ability to self-synchronize with each other, independently determine master and slave modes of operation to cooperate as a network, and independently vary those functions to adjust to changes in the network.

Abstract: Apparatus and methods for clock and data recovery are disclosed. In one embodiment, a clock and data recovery system includes a sampler, a deserializer, a phase detector and a frequency detector. The sampler may be configured to sample a serial data stream to produce data samples and transition samples. The deserializer may be configured to deserialize the data samples and the transition samples to produce deserialized data samples and deserialized transition samples. The deserialized data samples and the deserialized transition samples can be aligned and provided to the phase detector and the frequency detector, thereby improving phase alignment and cycle slip detection.

Abstract: Apparatus and methods for rotational frequency detection are disclosed. In one embodiment, a rotational frequency detector is configured to receive samples taken from a serial data stream and to generate a frequency up error signal or a frequency down error signal. The rotational frequency detector processes a first set of samples to generate first transition data, which may be stored in a memory. The rotational frequency detector processes a second and third set of samples to generate second and third transition data. The frequency up or frequency down error signal is generated based at least partly on the first, second or third transition data. This configuration can reduce the maximum operating frequency of the rotational frequency detector, thereby simplifying the rotational frequency detector design to a point that a conventional static digital CMOS circuit design flow can be used to design the rotational frequency detector.

Abstract: The present invention provides a method, an apparatus, and a system for time synchronization of an xDigital Subscriber Line (xDSL). The method includes: transmitting, by a customer premises equipment (CPE), a first symbol to a central office (CO) equipment, and obtaining time Ts2 indicating the moment that the first symbol is transmitted; receiving, by the CPE, a second symbol transmitted by the CO, and obtaining time Ts1 indicating the moment that the second symbol is received; obtaining, by the CPE obtains time Tm2 indicating the moment that the first symbol is received by the CO and time Tm1 indicating the moment that the second symbol is transmitted by the CO; the CPE calculates an offset between a clock of the CPE and a clock of the CO according to Ts1, Ts2, Tm1, Tm2 and a delay of the CPE; and the CPE adjusts the clock of the CPE according to the offset to achieve synchronization.

Abstract: Computer-readable media, apparatus and other embodiments associated with performing comma alignment with scrambled data are described. One example method includes controlling an apparatus to generate a data stream that facilitates achieving and determining alignment in a device. The data stream includes sequences of N random portions of Y-bit characters followed by a Z-bit alignment character, N, Y and Z being integers. Another example method includes controlling an apparatus to receive and examine the data stream. The method also includes generating an alignment signal upon determining an alignment for recovered data in the device.

Abstract: A signal receiving apparatus 2 has a memory circuit 22, writing of data contained in a digital input signal transmitted from a signal transmitting apparatus 1 is performed using a clock signal separated and created by a PLL circuit 21 from the digital input signal received, and reading is performed using a reference clock signal with quartz accuracy from a reference clock generating circuit 24. To reproduce the digital input signal by correcting the shift between the clock signal and the reference clock signal, the signal receiving apparatus detects the shift between the two clock signals. When the signal receiving apparatus 2 side lags behind the signal transmitting apparatus 1, the data contained in the digital input signal undergoes thinning out, and when it leads, a signal generated from previous and subsequent digital input signal is interpolated.

Abstract: A linear phase detector includes an up/down pulse generator operating in response to received data signals and a recovered clock signal. The phase detector generates up and down pulses that have pulse widths proportional to the phase differences between transitions of the received data signals and edges of the recovered clock signal. By generating up and down pulses using a linear phase detector in proportion to a phase error, data signals are effectively recovered, even data signals with significant jitter.

Abstract: A method and apparatus for identifying and tagging a target, such an individual or an item, are described that provide an improved mechanism for identifying the target without alerting the target. In this regard, a method and apparatus can irradiate the target so as to create a radioisotope signature for the target. By thereafter monitoring the radioisotope signature, the target can be identified and tracked in a covert manner.

Abstract: A control rod position detector including a permanent magnet that is attached on a control rod inserted in a reactor pressure vessel, where the permanent magnet is capable of moving together with the control rod, and a plurality of reed switch mechanisms that are arranged in the reactor pressure vessel at regular intervals in an insertion direction of the control rod. Each of the reed switch mechanisms is provided with a pair of reed switches that are placed so as to overlap with each other in the insertion direction of the control rod. The pair of reed switches are connected to a common wiring. The common wiring is connected to a detector that detects a position of the control rod based on signals from the reed switches.

Abstract: An apparatus for inspecting and testing a startup range neutron monitoring system for a nuclear reactor. The apparatus includes: a neutron-flux detector; a preamplifier that amplifies an electric signal output from the neutron-flux detector; a pulse measurement unit that counts times when electric signal output from the preamplifier exceeds a discrimination voltage; a discrimination-voltage setting unit that applies the discrimination voltage to the pulse measurement unit; a voltage-setting unit that applies a voltage to the neutron-flux detector; an arithmetic processing unit that calculates an output power of the reactor based upon an output signal of the pulse measurement unit; an output unit that outputs data representing the output power of the reactor, calculated by the arithmetic processing unit; and an inspecting/testing unit that sets the discrimination voltage and the voltage to be applied by the voltage-setting unit.