Transmitter. 4.1.1.1 Output Spectrum [***]
Transmitter. The transmitter converts the digitized output waveform, received from the base radio controller via the dedicated high speed serial link, into a high power RF signal. The transmitter includes a 800 MHz band linear power amplifier. The linear 350 Xxxxx PEP power amplifier provides 60 dB IMR and is rated for 70 Xxxxx average continuous duty. The high level of linearity is achieved with a double conversion feedback design using a number of custom integrated circuits. The transmit frequency is controlled through the on-board synthesizer. The BRC is used to perform thermal derating, transmitter initialization, power control loop leveling and synthesizer loading. This module includes fans for thermal management.
Transmitter. 4.6.1. Seller has a valid, binding and enforceable leasehold interest, which is free and clear of all Liens except for Permitted Liens, in and to the Leased Transmitter Site.
Transmitter. No employee may work on the Mt. Xxxxxx transmitter while power is applied to the equipment without another qualified member of the Engineering Department being present. No employee shall be required or requested to climb a transmitter tower. No employee at the main transmitter may, unless another qualified member of the Engineering Department is present:
Transmitter. The transmitter must be of type magnetron with solid state modulator, or semiconductor; • RF magnetron must have a minimum life time of 50,000 hours; • transmitting frequency must be in the Ka-band, adjustable in the range 35 to 37 GHz, or in the W band in the range of 93 to 97 GHz; • The pulse transmit power must be at least 25 kW, the stability of the transmitted power must be 0.2 dB in the normal operating conditions and the time interval of one month, in case of FMCW solution the transmitter power must be at least 0.5 W; • The length of the pulse transmitter pulse mode must be within the range of 150 to 300 ns; • Repetition rate (pulse repetition frequency, PRF) for pulse mode must be user- adjustable from a minimum of 3-10 kHz, switching frequency must be possible by software settings within the measurement scenarios without hardware intervention;
Transmitter. Transmitter must be semiconductor or of type RF magnetron (minimum life time of 50,000 hours); • Transmitting frequency must be in the X-band and at least three frequencies within the X-band must be offered by the Supplier; • In case of delivery of a FMCW solution, the transmitter power must be at least 4 W and the stability of the transmitted power must be 0.2 dB in the normal operating conditions and time interval of one month; • Length of the transmitted pulse must be at least in the range of 0.5 to 20 µs; • Repetition rate (pulse repetition frequency, PRF) for pulse mode must be user- adjustable within 1-2 kHz. It must be possible to switch the frequency by using software settings within the measurement scenarios without hardware intervention.
Transmitter. Centre Wavelength λc λc-6.5 λc λc+6.5 nm Spectral Width (-20dB) ∆λ 1 nm Side Mode Suppression Ratio SMSR 30 dB Average Output Power Pout -5 0 dBm 1 Extinction Ratio ER 9 dB Optical Rise/Fall Time (20%~80%) tr/tf 180 ps Data Input Swing Differential VIN 400 1800 mV 2 Input Differential Impedance ZIN 90 100 110 Ω TX Disable Disable 2.0 Vcc V Enable 0 0.8 V TX Fault Fault 2.0 Vcc V Receiver Receiver Sensitivity -23 dBm 3 Receiver Overload -3 dBm 3 LOS De-Assert LOSD -24 dBm LOS Assert LOSA -35 dBm LOS Hysteresis 1 4 dB Data Output Swing Differential Vout 370 1800 mV 4 LOS High 2.0 Vcc V Low 0.8 V Notes:
Transmitter. OFDM-CSK with a discrete chaotic sequence for modulation is considered in the system, with respect to the non-coherent advantages of DCSK and the spectral efficiency of multi-carrier modulation. For mathematical simplification, a mathematical model is described for a single user only. As shown in Figure 4.3, for each user, a chaotic code is generated and used as a reference and spreading code. The input information sequence is first converted into U parallel data sequences Figure 4.2: Three layers of security with each bit being of equal probability of +1 and -1. Figure 4.3: Block diagram of the OFDM-CSK transmitter Let S be the U × U scrambling matrix, which is obtained by the logistic map-based chaotic sequence xc, generated from the chaotic signal generator. Also let s = [s1, s2, · · · , sU ]T and e = [e1, e2, · · · , eU ]T represent the data vectors before and after scrambling (the first layer of security), respectively. It holds that e = s × S. (4.1) The uth sub-stream is spread with the chaotic spreading code au = [au,1, au,2, · · · , au,β] (generated by the same chaotic signal generator) through the chaotic reference signal ∑ β xu(t) = au,kh(t − kTc), (4.2) k=1 where h(t) is the square-root-raised-cosine filter, βis the length of chaotic spreading code and Tc is the chip duration. This filter is band-limited and is normalised to have unit energy. Let H(f ) = F (h(t)), where F denotes the Fourier transform. It is assumed that H(f ) is limited to [−Bc/2, Bc/2] , which satisfies the Xxxxxxx criterion with a roll-off factor α (0 < α < 1). Here, Bc = (1 + α)/Tc. Note that the first two subcarriers are used to modulate the reference signals xu(t) and xc(t). The remaining subcarriers are used to carry data. Therefore, the transmitted signal of the single-user OFDM-CSK after the second layer of security is given by e(t) = xc(t) cos (2πf1t + φ1) + xu(t) cos (2πf2t + φ2) ∑ U + eixu(t)cos(2πfi+2t + φi+2), (4.3) i=1 where φi represents the phase angle introduced in the carrier modulation process of the ith subcarrier (with frequency fi). In this chapter the transmitted energy in every subcarrier is normalised.
Transmitter. The radio or telephone transmitter installed at the Premises to convey an activation signal to the Alarm Receiving Centre. Any radio transmitters will at all times remain the property of KNI and the supplier of the radios.
Transmitter. The Company undertakes to install signalling equipment for the monitoring of the alarm system installed at the premises in the central station of the company or his sub-contractor. Signalling equipment shall mean such equipment as defined and prescribed in terms of the by-laws of South Africa.
