摘要:
In a communication system including at least one transmitter and at least one receiver, a frequency offset between a carrier frequency of the transmitter and a local frequency reference of the receiver is estimated. A phase difference is computed between successively collected samples of a frequency synchronization signal transmitted by the transmitter and detected by the receiver. The phase difference is added to accumulated phase differences. Phase differences of successively collected samples are computed and added to accumulated phase differences until M accumulated phase differences have been added. The sum of the M phase differences is dumped, resulting in zero accumulated phase differences. Phase differences of successively collected samples are computed, the phase differences are added to accumulated phase differences, and the sum of M phase differences is dumped until N sums of M phase differences have been dumped. The N sums of the M phase differences are added to produce the estimated frequency offset.
摘要:
The novel blend comprises:(A) from 1 to 99% by weight of at least one thermotropic-liquid-crystalline polyester and/or polyesteramide and(B) from 1 to 99% by weight of at least one sulfoxide group-containing polymer,in each case based on the total weight .SIGMA.�(A)+(B)!. Component (B) is a linear and/or branched polymer having a mean molecular weight M.sub.w in the range from 4,000 to 200,000 comprising recurring units of the formula �--F--S).sub.c --(F--SO).sub.d --!, where F, independently of one another, are simple or para-, meta- or ortho-linked arylene systems having 6 to 18 carbon atoms, preferably phenylene, naphthylene or biphenylene, where the sum c+d is 1, with the proviso that d is always .gtoreq.0.70. Component (A) is a thermotropic liquid-crystalline polymer having a mean molecular weight M.sub.w in the range from 10,000 to 200,000 g/mol and a transition temperature of >250.degree. C., and/or an amorphous thermotropic liquid-crystalline polymer having a mean molecular weight M.sub.w of from 10,000 to 200,000 g/mol and a glass transition temperature of >160.degree. C.
摘要:
Molding composition based on fluoropolymers and process for producing foam material therefrom The invention relates to a molding composition based on fluoropolymers which additionally contain from 1 to 50% by weight of at least one polymer containing sulfoxide groups. The polymer containing sulfoxide groups comprises, in particular, polyarylene sulfoxide units of the formula: --(--C.sub.6 H.sub.4 --SO--)--.
摘要:
In the process for the surface oxidation of polyarylene thioethers, the surface of the material to be oxidized is brought into contact with an ozone-containing gas or a liquid. The materials prepared by the process can be used in aircraft construction, automobile construction and chemical apparatus construction.
摘要:
The invention relates to a transmission system comprising a phase-locked loop (12) which includes a phase comparator (15) for comparing an oscillator signal with a reference signal and for generating a comparison signal, and an oscillator which is provided for receiving a control signal derived from the comparison signal. The oscillator arranged as a ring oscillator (14) comprises at least one delay element (27 to 31) included in a closed circuit. At least one delay element (27 to 30) has at least two different adjustable delay times. A controller (19) is provided for setting the delay times of at least one delay element (27 to 30) in dependence on the comparison signal.
摘要:
A mobile radio receiver for a digital radio transmission system includes a recognition arrangement (6) for searching a received digital signal for pulses (i) of a frequency correction burst which recurs with a predetermined frequency in the digital signal and for determining the pulse positions (t). A frequency estimation arrangement (7) derives estimates of the predetermined frequency. In order to improve the initial synchronization of the mobile radio receiver with a base station, the recognition arrangement includes an averaging circuit (14) which averages with weight factors (Us) the pulse positions (t) that have been determined in successive observation intervals, the weight factors (Us) being proportional to the individual pulse heights (U). The reliability of recognition of pulses which belong a frequency correction burst is improved by providing evaluation based on the number of pulses of amplitudes above a selected threshold level during a selected interval, and further evaluation based on a phase error quality of the frequency estimates of the predetermined frequency.
摘要:
A method, a computer program product and a device for requesting access to a node (BS) of a wireless communications network (10) are described. In the network (10) identification codes are used to differentiate access requests of different network components (UE). The method comprises the step of determining information about a transmission path (12) to e.g. the network node (BS), the step of determining an identification code in dependence on the determined transmission path information, wherein previously an association between identification codes and transmission path information has been established, and the step of modulating the selected identification code onto a signal to generate an access request signal carrying transmission path information.
摘要:
Membranes for use in polymer electrolyte fuel cells or electrolyzers comprise a sulfonated aromatic polyether ether ketone of the formula (I) wherein the ion exchange equivalent (I.E.C.) of the sulfonated polyether ether ketone is in the range from 1.35 to 1.95 mmol (—SO3H)/g (polymer) and the membrane has a long-term stability of at least 1000 hours at an operating voltage of from 0.4 to 1.1 V.
摘要:
The invention relates to a sensor comprising a piezoelectric crystal with a polyarylene thioether-containing coating, the coating containing at least one polyarylene system having repeating units of the formula I, —[(Ar1)n—X]m—[(Ar2)i—Y]j—[(Ar3)k—Z]l—[(Ar4)o—W]p— (I) which contain at least one thioether group, in which Ar1, Ar2, Ar3 and Ar4 are identical or different aryl systems having from 6 to 18 carbon atoms, W, X, Y and Z are identical or different linking groups, selected from the group comprising —SO2—, —S—, —SO—, —O—, —CO—, —CO2—, alkylene or alkylidene having from 1 to 6 carbon atoms and —NR1—, where R1 is an alkyl or alkylide group having from 1 to 6 carbon atoms and at least one linking group must be —S—, n, m, i, j, k, l, o, p are, equal or different, integers zero, 1, 2, 3 or 4, their sum having to be at least 2, and to the use thereof.
摘要翻译:本发明涉及包含具有聚亚芳基硫醚的涂层的压电晶体的传感器,该涂层含有至少一个具有式I重复单元的聚亚芳基体系,其含有至少一个硫醚基团,其中Ar 1,Ar 2,Ar 3和Ar 4 是具有6至18个碳原子的相同或不同的芳基系统,W,X,Y和Z是相同或不同的连接基团,选自-SO 2 - , - S - , - SO - , - O - 具有1至6个碳原子的-CO-,-CO 2 - ,亚烷基或亚烷基和-NR 1 - ,其中R 1是具有1至6个碳原子和至少一个连接基团的烷基或亚烷基基团必须是-S-,n ,m,i,j,k,l,o,p等于或不同,整数0,1,2,3或4,它们的和必须至少为2,并且与其使用有关。
摘要:
A method for removing oxides of nitrogen from gases and liquids by contacting a NO.sub.x containing gas or liquid with a polyarylene thioether filter material and a solid oxidizing agent having an electron potential greater than 0.96 V, wherein the solid oxidizing agent oxidizes NO into NO.sub.2 which is removed by the polyarylene thioether filter material.