Abstract: In general, this disclosure relates to techniques for adaptively determining a rate for intra-coding segments (e.g., macro-blocks) of video data within a sequence of video units (e.g., frames) in response to the receipt of error feedback that is provided by a video decoder. One example method includes receiving feedback from a video decoder that indicates an error associated with coded video data, and, upon receipt of the feedback, determining a rate for intra-coding a specified number of segments of video data for each video unit within a sequence of video units, wherein an intra-coding of segments of video data within one video unit is independent of a coding of segments of video data within other video units within the sequence.

Abstract: The present invention provides a method and apparatus for encoding video content into a novel temporal layered coding structure. In one embodiment of the present invention, a plurality of sub-sequence layers are defined in a layer hierarchy in accordance with the present invention. A plurality of images within a sub-sequence of a group of images are selectively assigned to a respective one of the sub-sequence layers. A grouping of images contained in any sequential combination of sub-sequence layers that includes a hierarchically lowest of the sub-sequence layers results in a group of images that temporally are substantially evenly spaced. A related method and apparatus for decoding the temporally layered video content are also disclosed.

Abstract: An improved MPEG adaptive reference fine granularity scalability encoder and decoder is described. The parameters ? and ? used to weight difference data during the generation of a prediction error signal in an enhancement layer are modified in dependence upon the magnitude of the values in the difference data.

Abstract: In a motion estimation device and a video encoding device including the same, a motion estimation device provides a motion vector by performing a motion estimation algorithm, and includes a motion estimation unit including a plurality of processing elements that perform a calculating operation on pixel data of a block of a current frame and reference data in a search area of a reference frame and that output a plurality of operation results on a plurality of candidate blocks in the search area, in parallel; and a comparison and selection unit that compares the operation results provided from the motion estimation unit to each other, and that generates and outputs a motion vector corresponding to the block of the current frame.

Abstract: The present invention relates to an encoding system for encoding input video data and a multiplexing system for multiplexing a plurality of encoded streams. More particularly, it proposes a system and method that involve describing, in encoded streams, information on the picture order of input video data, and using the picture order information when generating packetized elementary stream (PES) packets, to prevent delays associated with the PES packet generation. MPEG encoders generate PTS_count and DTS_count based on the information obtained from the number of fields in the input video data and describe the PTS_count and DTS_count data as picture order information in encoded streams. The packetizers for generating packetized elementary stream take out PTS_count and DTS_count described in the encoded streams, generate presentation time stamps and decoding time stamps based on PTS_count and DTS_count, and add these time stamps as PES header data.

Abstract: This invention enables to generate encoded data without noticeable image quality degradation when reproducing an image at a lower resolution not to mention the original resolution. An image a digital camera can capture takes three sizes L, M, and S. When the size L is designated, stream conversion information SC is set to “2”. When the size M is designated, the stream conversion information SC is set to “1”. When the size S is designated, the stream conversion information SC is set to “0”. When encoding image data in compression processing, block overlap processing of suppressing discontinuity of data at the boundary between adjacent blocks is executed as many times as the count set in the stream conversion information.

Abstract: A decoder which can detect errors in MPEG-2 coefficient blocks can identify syntactically-correct blocks which have out-of-bounds coefficients. The decoder computes coefficient bounds based on quantization scalers and quantization matrices and compares these to coefficient blocks during decoding; if a block has out-of-bounds coefficients, concealment is performed on the block. In a decoder implemented all in software, coefficient bounds checking is performed on iDCT coefficients against upper and lower bounds in a spatial domain. In a decoder which performs iDCT in hardware, DCT coefficients are compared to an upper energy bound.

Abstract: Systems and methods for monitoring impulse noise are described. At least one embodiment is a method, which comprises detecting whether impulse noise is present and in response to detecting the presence of impulse noise, performing time domain analysis to determine whether one or more impulse noise sources are present based on minimum interarrival time and maximum impulse length. The method further includes performing frequency domain analysis to estimate frequencies associated with the one or more impulse noise sources and based on the time domain analysis and frequency domain analysis, providing a total number of impulse noise sources and frequencies associated with the impulse noise sources. In this regard, the embodiments described herein provide dual-speed monitoring of impulse noise in the form of short-term and long-term monitoring.

Abstract: A method of modulation mode detection for a communication system including at least a channel transmitting signals utilizing a target modulation mode is provided. The method includes: (a) selecting a default modulation mode for the channel; (b) estimating a timing frequency offset (TFO) of the channel of the communication system for obtaining at least a TFO value and storing the TFO value; (c) comparing the TFO value with a first predetermined value to generate a comparison result; and (d) determining whether the default modulation mode is substantially identical to the target modulation mode according to the comparison result.

Abstract: A transmitting apparatus capable of enhancing the certainty of data transmission of MIMO system, improving the system throughput, and providing a retransmission technique adaptive to the multi-antenna transmission. In this apparatus, a serial/parallel converting part (300) serial/parallel converts the data, which is to be transmitted, into a number nT of data substreams. A data rearranging part (301) rearranges, based on feedback information, the nT data substreams. CRC encoding parts (302) CRC encode the respective data substreams. Modulating/encoding parts (303) modulate and encode the respective corresponding data substreams. A number nT of transmission antennas (304) transmit the data substreams.

Abstract: An apparatus, method, and system for reducing a C/N in an OFDM receiver using diversity combining techniques in the presence of ICI, wherein the apparatus comprises an encoded data estimator adapted to estimate data received in the OFDM receiver; a pair of ICI estimators operatively connected to the encoded data estimator and adapted to calculate an inter-carrier-interference term of the data; and a pair of diversity combining equalizers adapted to compensate multi-path interference of the data, wherein a first one of the diversity combining equalizers is operatively connected to the encoded data estimator, and a second one of the diversity combining equalizers is operatively connected to the pair of ICI estimators. The diversity combining equalizer may comprise a MRC diversity combining equalizer. Preferably, the encoded data estimator, the pair of ICI estimators, and the pair of diversity combining equalizers are implemented on a DVB-T/H diversity SoC.

Abstract: A technique for re-acquiring a symbol index in the presence of sleep timer errors in a MediaFLO™ (Forward Link Only) mobile multimedia multicast system comprising a receiver and a transmitter, wherein the method comprises receiving a digital signal comprising a superframe comprising one or more Orthogonal Frequency Division Multiplexing (OFDM) symbols in the receiver comprising a timer; waking up the receiver from a sleep mode of operation by an amount of time equal to a maximum error introduced by the timer plus a time to reacquire a beginning of each OFDM symbol plus a time to reacquire a symbol index; and reacquiring the symbol index.

Abstract: A technique for estimating a carrier frequency offset and a timing offset in a MediaFLO™ (Forward Link Only) system, wherein the method comprises receiving Orthogonal Frequency Division Multiplexing (OFDM) symbols; interpolating pilots on odd or even symbols of the received OFDM symbols; determining a phase difference between two successive symbols using the interpolated pilots; obtaining an estimate of the carrier frequency offset and the timing offset from the determined phase difference between two successive symbols; and correcting a sampling frequency in accordance with the estimated carrier frequency offset and timing offset.

Abstract: Respective codewords of quantization codebooks corresponding to a number of data streams are selected based on channel information estimated by a received training symbol. A stream mode is selected among stream modes to determine a modulation method applied to each data stream. The data stream is detected by using the codeword corresponding to the quantization codebook of the data stream corresponding to the selected stream mode as a precode matrix, and the detected data stream is modulated. In this case, a receiving apparatus performs a feedback operation so that indexes of the selected stream mode and the codeword used as the precode matrix may be transmitted to the transmitting apparatus. The transmitting apparatus selects the number of transmitted data streams and the modulation method based on the transmitted index of feedback streams by the feedback operation.

Abstract: A method of shaping an orthogonal frequency division multiplexing (OFDM) signal spectrum of a transmitted signal is disclosed. An input signal including an input component is received and a first instance of the input component is generated. The method also includes determining that a second instance of the input component is to be different than the first instance. The second instance of the input component that is different from the first instance is generated. An output signal to be transmitted is generated and includes the first instance and the second instance of the input component.

Abstract: An apparatus and method for detecting signals based on a Lattice Reduction (LR) algorithm in a Multiple Input Multiple Output (MIMO) wireless communication system are provided.

Abstract: A method and apparatus for transmitting signals in a multi-hop wireless communication system are provided. A first BS transmits a signal including a first common information codeword and a first private information codeword. A second BS transmits a signal including a second common information codeword and a second private information codeword. A first RS joint-decodes the first common information codeword and the second common information codeword and decodes the first private information codeword. A second RS joint-decodes the first common information codeword and the second common information codeword and decodes the second private information codeword.

Abstract: A wireless communication device is provided that includes: a plurality of receiving portions that respectively receive wireless signals that are transmitted based on frequency-use methods set from among a plurality of frequency-use methods; and a setting portion that sets one of the plurality of frequency-use methods on each of the plurality of receiving portions respectively. The setting portion changes the frequency-use method of the plurality of receiving portions, based on a receiving result of a wireless signal in each of the plurality of receiving portions.

Abstract: The present invention provides a transmission method and apparatus for cancelling inter-carrier interference in wireless communication systems. Particular carriers are not used for data transmission but carry weighted data to cancel the ici interference of a first group of interfering sub-carriers onto a second group of victim sub-carriers. The weights are inversely proportional to the frequency offset between the interfering sub-carriers and the victim sub-carriers.

Abstract: A receiving apparatus and method of a Maximum Likelihood (ML) scheme in a Single-Carrier (SC) system are provided. The apparatus includes at least two antennas, at least two Orthogonal Frequency Division Multiplexing (OFDM) demodulators, at least two subcarrier mappers, at least two OFDM modulators, and a detector. The antennas receive signals. The OFDM demodulators convert the signals into frequency domain signals. The subcarrier mappers confirm signals mapped to frequency domain subcarriers. The OFDM modulators convert the signals into time domain signals. The detector constructs at least one set for candidate transmission symbols and detects receive signals through ML detection using the set.

Abstract: Provided is a method of controlling a multiple input multiple output (MIMO) system. One embodiment of the method includes the steps of: estimating, at a receiver, a MIMO channel and detecting data streams using a successive interference cancellation scheme; calculating, at the receiver, S and P using the estimated channel and then feeding back information corresponding to (P1, P2, . . . , PM-1, SINR5M) to a transmitter, and determining, at the transmitter, a transfer rate and transmission power perstream using the fed-back information.

Abstract: The present invention, generally speaking, provides interleavers and methods of interleaving that satisfy the need for backward compatibility while effectively addressing competing design objectives. In accordance with one aspect of the invention, data is transmitted using a number of transmit antennas greater than an expected number of receive antennas. At least one pair of transmit antennas is formed, and multiple second data streams are formed from a first data stream, successive bits in said first data stream being assigned to different ones of said second data streams. Block interleaving of multiple respective ones of said second data streams is individually performed. During successive transmission intervals, the pair of transmit antennas is used to transmit a pair of data symbols taken from different ones of said second data streams, followed by an equivalent transformed pair of data symbols.

Abstract: A detecting method of a multiple-input multiple-output system includes the steps of: a) canceling interference between transmit signals by assigning weight values to signals received through a plurality of antennas, and determining K optimal antenna signals through channel gain estimation; b) calculating L transmit signal estimation values by quantizing the optimal antenna signals according to a predefined constellation size of L; c) calculating L residual antenna signals, in which interference of the transmit signal estimation values is removed from the received signals using the L Tx signal estimation values; d) calculating L residual transmit signal estimation values by quantizing the L residual antenna signals according to the predefined constellation size; and e) creating K×L estimated transmit signal candidate groups by repeating the calculation of the L residual transmit signal estimation values for each of the K optimal antenna signals, and detecting transmit signals from the estimated transmit signal

Abstract: An apparatus and method for beamforming in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. A Base Station (BS) includes a calculator for generating relational expressions between beamforming vectors of Mobile Stations (MSs) using channel information of each MS, for determining beamforming vector candidates of each MS from the relational expressions using generalized Eigen-analysis, and for selecting beamforming vectors for each MS from the beamforming vector candidates, and a plurality of Transmit (Tx) beamformers for performing Tx beamforming on dedicated pilot symbols to be transmitted to each MS using the beamforming vectors for each MS.

Abstract: The present invention relates to a control method for a communication network that has a transmitter with an array of transmit antennas and that has at least one receiver communicating with the transmitter. The receiver performs a channel measurement for a receive antenna of the receiver using a signal transmitted from the transmitter to the receiver. The receiver further determines channel coefficients for each of an array of transmit antennas at the transmitter from an output of the channel measurement, and then applies a linear, reversible and orthogonal transform to the channel coefficients, thus ascertaining channel component coefficients indicative of the individual weight of respective channel components in a transform domain. The receiver then selects one or more channel components in the transform domain and communicates to the transmitter a control signal indicative of one or more preferred channel components or a magnitude of one or more channel component coefficients, or both, in quantized form.

Abstract: A communication channel has a highly linear switched current mixer that incorporates passive filtering (e.g., low pass, notch) for improved transmitting (Tx) and receiving (Rx) with adding external filtering components. A high IIP2 (input referenced second order intercept point) of the receiver at the Tx offset is essential to avoid corrupting the system's sensitivity performance, and a high triple beat (TB) is required to avoid sensitivity degradation due to transmitter leakage. Thanks to the embedded filtering in the mixer and the active post-distortion (APD) method in a low noise amplifier (LNA), the required high linearity is achieved with low noise figure and power consumption, overcoming transmitter power leakage without the use of a SAW (surface acoustic wave) filter.

Abstract: A digital broadcasting system and method of processing data therein are disclosed.

Abstract: A transmitter and/or receiver for performing frequency domain equalization is provided. A transmitter includes a pilot position determination unit for determining positions for inserting pilots in a frequency domain based on frequency spectrums of data, and a pilot insertion unit for inserting the pilots between the frequency spectrums of the data according to the determined positions for inserting the pilots.

Abstract: Methods and apparatus for predistorting signals in a polar modulation transmitter. An exemplary method includes predistorting an envelope component signal in an amplitude path of a polar modulation transmitter according to a set of AM/AM predistortion coefficients, and predistorting a phase component signal in a phase path of the polar modulation transmitter according to a set of AM/PM predistortion coefficients. The AM/AM and AM/PM predistortion coefficients are stored in a memory in the form of a look up table (LUT). The envelope component signal is scaled and/or offset, before predistortion is applied, by an amount dependent upon which average power level of a plurality of average power levels the power amplifier of the polar modulation transmitter is configured to operate. Scaling and/or offsetting the envelope component signal prior to applying predistortion affords the ability to share the AM/AM and AM/PM predistortion coefficients of the predistortion LUT over the plurality of average power levels.

Abstract: A technique of acquisition in a MediaFLO™ (Forward Link Only) mobile multimedia multicast system, wherein the method comprises receiving a superframe comprising a first digital symbol in a receiver operating in a first state of operation; assuming the first received digital symbol to be a Time Division Multiplexed (TDM) pilot symbol; calculating a first sparseness index of the first symbol; storing the first sparseness index; operating the receiver in a second state of operation; receiving a second digital symbol; calculating a second sparseness index for the second digital symbol; the receiver remaining in the second state of operation when the second sparseness index is greater than the first sparseness index, wherein the second digital symbol is assumed to be the TDM pilot symbol; and verifying that the last assumed TDM pilot symbol is the correct TDM pilot of the superframe.

Abstract: A multiple-input-multiple output (MIMO) transmitter for transmitting an orthogonal frequency division multiplexed (OFDM) symbol over a plurality of spatial channels using a plurality of antennas is described. The transmitter includes encoding circuitry to encode blocks of input bits in accordance with a variable encoding rate to generate blocks of encoded bits and a spatial-frequency parser to parse the blocks of encoded bits into spatial-frequency groups. The transmitter also includes subcarrier modulators to modulate each spatial-frequency group of encoded bits on one of the OFDM subcarriers to generate symbol-modulated subcarriers. Spatial-frequency groups having a greater number of encoded bits are modulated at higher-order modulation levels and spatial-frequency groups having a lesser number of encoded bits are modulated at lower-order modulation orders.

Abstract: A pulse signal reception device of a comparatively simple configuration detects a signal sampled at an optimal clock timing for a pulse modulation signal having a signal width shorter than a symbol frequency. In this device, a time division unit (103) samples a data signal at a clock signal rise edge and outputs the sampled data signals to counters (104-1 to 104-3), respectively. The counters (104-1 to 104-3) count the number of High levels when the data signal becomes High level within a predetermined period, and a maximum value detection unit (105) outputs maximum data string information on a data string counted by a counter in which the maximum number of High levels has been detected among the counters (104-1 to 104-3) to a selection data judgment unit (106). The selection data judgment unit (106) judges which data string sampled at a particular timing is to be selected as a demodulation data string.

Abstract: A receiving device that receives as a received signal R? a transmission signal T? (T?=a1e1?+a2e2?+ . . . +akek?) obtained by multiplying k (k is a positive integer) linear independent signal vectors {ei?|i is an integer satisfying 1?i?k} by a transmission information coefficient {ai|i is an integer satisfying 1?i?k and ai is a real number} is disclosed. The receiving device includes: a template generating unit that generates m (m is a positive integer) linear independent template vectors {pi?|1?i?m}; a correlation unit that calculates a correlation value {ci=(R?,pi?)|1?i?m} between the received signal R? and the template vector {pi?} and outputs a correlation value vector c? (c1, c2, . . . , cm); and a multiplying unit that multiplies a transposed matrix of a matrix [??] by the correlation value vector c?.

Abstract: Method for generating reference signal sequence using grouping is explained. In this method, base sequences are grouped such that each group contains at least one base sequence of each length, so UE(s) can use various length sequences as a reference signal. And in this method, inter cell interference caused by using various length sequence as a reference signal sequence can be minimized by grouping sequences having the high cross correlation relation.

Abstract: A wireless communication system, an apparatus and a method for processing a received OFDM signal is provided. The wireless communication system comprises an interface and a processing apparatus. The interface is configured to receive a received OFDM signal. The processing apparatus comprises an estimation module and a calculation module. The estimation module is configured to estimate an auto-correlation matrix relating to the received OFDM signal, with the auto-correlation matrix comprising a plurality of elements. Then, the calculation module is configured to calculate an amplitude and a phase for each of the elements to determine the carrier frequency offset (CFO) and timing offset (TO) of the received OFDM signal according to the amplitudes and phases. By exploiting the auto-correlation matrix of the received OFDM signal, the CFO and TO can be derived efficiently.

Abstract: Timing and frequency offset processing in sub-carriers is performed in an Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) receiver system. Sub-carriers are divided into two sub-sets, where the sub-sets contain an equal number of sub-carriers. Subsequently bad sub-carriers are removed, if present, from first sub-set of the sub-sets, and corresponding sub-carriers from a second sub-set of the sub-sets are also removed. Further, a phase difference on each sub-carrier from each sub-set is computed, and mean phase differences of each of the sub-sets are computed. Furthermore, frequency offset is computed by averaging the mean phase differences of the sets.

Abstract: A technique for estimating maximum Doppler frequency of a wireless signal in a wireless communication system, wherein the method comprises receiving a wireless signal; determining an impulse response of the received wireless signal; determining an auto-correlation function (ACF) value of the impulse response of the received wireless signal; determining a power spectrum density of said received wireless signal based on the ACF value; and selecting an algorithm for performing demodulation of the received wireless signal by utilizing the determined power spectrum density.

Abstract: A radio integrated circuit includes, in part, an analog front end block, an analog-to-digital converter responsive to the analog-front end block, a digital signal processor responsive to the analog-to-digital converter and adapted to generate in-phase and quadrature signals, and a serial communication interface configured to receive and transmit the in-phase and quadrature signals. The serial communication interface supplies a gain control signal to the analog front end block when a switch disposed in the radio integrated circuit is in a first position. When the switch is in a second position, a gain control block disposed in the radio integrated circuit receives a gain control signal from the analog-to-digital converter and supplies the gain control signal to the analog front end block. The digital signal processor may be configured to interleave the in-phase and quadrature signals.

Abstract: Embodiments for clock and/or data recovery may comprise two samplers to sample a relatively small number of distinct data sample phase locations of a data pulse relative to an estimate of the location of a center of the data pulse.

Abstract: An arrangement for synchronizing a transmission time of a digital data stream in individual high-frequency transmitters of a common-wave network operating according to an ATSC standard and transmitting identical data at an identical frequency. The stream generated in a master station is supplied to the transmitters as a periodic succession of data frames, and a setpoint transmission time is calculated in the transmitters from a synchronizing time stamp inserted into the data frames within the master station and from a time reference used in the master station and transmitters, while the transmission of the frames by the transmitter is determined by a system clock in the transmitters. The setpoint transmission time is compared with the actual transmission time determined by the clock, and the clock frequency is regulated by a regulating circuit so that the actual transmission time determined by the clock corresponds with the calculated setpoint transmission time.

Abstract: A method of synchronizing two electronic devices connected by a wireless link with at least one path including a transmission channel and a reception channel. The two devices are included in a network, such as a mobile telephone network. Synchronization information is transmitted directly from one electronic device to the other, as a clock pilot signal, via the channels. After recovery, the clock pilot signal is used for synchronization of a reference frequency of the receiving electronic device.

Abstract: A data reception apparatus is disclosed. The data reception apparatus includes a strobe extractor for receiving a transmission signal and extracting a strobe signal from the transmission signal, the transmission signal including the strobe signal inserted between data signals and a clock signal following the strobe signal, the strobe signal having a different magnitude from a magnitude of a data signal, and the clock signal having an equal magnitude to the magnitude of the data signal, a clock recoverer for recovering the clock signal from the transmission signal, using the extracted strobe signal, and a sampler for sampling the data signals included in the transmission signal in response to the recovered clock signal. The probability of generating a timing skew error in the time interval between a clock signal and a data signal is minimized. Even though the level of a common component might change, the clock signal can be recovered accurately and the size of the clock recovery circuit can be reduced.

Abstract: A method of achieving reduced modulation range requirement in a Digitally Controlled Oscillator (DCO) which is deployed as part of a DRP (Digital Radio Processor) and tuned to a tuning frequency range having operating-channel center-frequencies, wherein phase difference between consecutive samples is termed as FCW (Frequency Control Word), uses the steps of digitally modifying and limiting the FCW so that the FCW does not exceed known FCW thresholds, e.g., chosen from ?/2, ?/4, ?/8, and redistributing the FCWs while maintaining a cumulative sum of phases and without significant EVM (Error Vector Magnitude) degradation. The FCW threshold can be chosen arbitrarily and need not be in the form of ?/2n. The method uses a FCW limiting algorithm which reduces supply voltage sensitivity of the DCO and enables significant reduction in area of capacitor bank which would be otherwise needed.

Abstract: The object of the present invention is to provide a data decision apparatus and an error measurement apparatus which can set the phase of the clock to the optimum state with respect to the data signal without continuously sweeping of the phase, and can keep the state for a long time.

Abstract: A first intensity Az expressed as Az=az×E?, a first reference intensity A0 expressed as A0=a0×E?, a second intensity Bz expressed as Bz=bz×E, and a second reference intensity B0=b0×E, are evaluated. The first intensity and the first reference intensity are of radioactive nuclides generated by a neutron capture reaction of a heavy nuclide or a fission product nuclide. The second intensity and the second reference intensity are of radioactive fission product nuclides except nuclides generated by a neutron capture reaction. The reference intensities are measured where the void fraction is known. Also a correlation curve of (az/a0) and a void fraction is evaluated. Finally an axial void fraction distribution is evaluated based on the value of (az/a0) and the correlation curve.

Abstract: An advanced digital rod position indication (ADRPI) system having rod drop monitoring capability. When a reactor trip occurs, the ADRPI system derives the rod drop time from the signals induced in the detector coils by the falling drive rods. The ADRPI system is linked to the reactor trip breaker to provide a reference point to allow accurate timing of the rod drop times.

Abstract: Exemplary embodiments provide automated nuclear fission reactors and methods for their operation. Exemplary embodiments and aspects include, without limitation, re-use of nuclear fission fuel, alternate fuels and fuel geometries, modular fuel cores, fast fluid cooling, variable burn-up, programmable nuclear thermostats, fast flux irradiation, temperature-driven surface area/volume ratio neutron absorption, low coolant temperature cores, refueling, and the like.

Abstract: A system and method for storing spent nuclear fuel that affords adequate cooling capabilities under “smart flood” criteria.

Abstract: A method for cleaning an irradiated nuclear fuel assembly includes chemically enhancing a technique utilizing an apparatus including a housing adapted to engage a nuclear fuel assembly. A set of ultrasonic transducers is positioned on the housing to supply radially emanating omnidirectional ultrasonic energy to remove deposits from the nuclear fuel assembly. Any corrosion products remaining after ultrasonic fuel cleaning will have exposed surfaces that are susceptible to chemical dissolution.

Abstract: A jet pump comprising: a nozzle apparatus having a header portion including, inside, a first pipe member forming a suction fluid passage for introducing suction fluid and the header portion surrounding the first pipe member, for introducing driving fluid, and a nozzle portion connected to the header portion, surrounding the first pipe member and forming an annular ejection outlet for ejecting the driving fluid; a jet pump body for mixing the driving fluid and the suction fluid sucked by the ejection of the driving fluid, and discharging the mixed fluid; and a second pipe member having one end connected to the nozzle apparatus, for introducing the driving fluid to the header portion, wherein the first pipe member is disposed through the one end inside a driving fluid passage formed in the second pipe member, and forms an opening portion of the suction fluid passage opened to the outside of the second pipe member; and the driving fluid passage is formed so that the driving fluid flowing toward the one end hi