Table of contents Introduction ........................4 Parts description of the coherent system ................ 6 WR-G65DDCe connectors ..................6 The WiNRADiO Coherence Clock & 1PPS Kit (WR-CC1PPS-210e) ...... 7 2.2.1.1 Coherent clock generator unit with 1PPS input ..........8 2.2.1.2 CLK OUT connectors for sampling clock output ..........9 2.2.1.3...
Kits have to be used. For more than sixteen channels please contact WiNRADiO. For coherent operation, all WR-G65DDCe receivers must be clocked at exactly the same frequency and phase. To achieve this requirement, it is necessary to distribute a sampling clock from a single low phase noise clock source.
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WR-G65DDCe Multichannel Coherent Application Guide Picture 1-2: An example of three WR-G65DDCe receivers in coherent configuration...
2 Parts description of the coherent system 2.1 WR-G65DDCe connectors The connectors required for coherent operation of the WR-G65DDCe receivers are shown in Picture 2-1 (present when the /CR option has been fitted): 1. CLK IN – ADC clock input 2.
The ‘WiNRADiO Coherence Clock & 1PPS Kit’ (hereafter referred to as the 'Kit') provides production and distribution of a coherent 210 MHz clock for up to eight WR-G65DDCe receivers as well as digital synchronization of the receivers. It also features an internal frequency reference of 0.1 ppm stability, input for external frequency reference and digital...
WR-G65DDCe receivers thus creating the coherent group of receivers. The unit generates a 210 MHz sampling clock for up to eight WR-G65DDCe receivers. The sampling clock is locked to a frequency reference, which can be internal or external. It also distributes a 1PPS trigger signal from the 1PPS input to all connected WR-G65DDCe receivers via the digital synchronization interface port SYNC OUT.
These are located on the top of the unit and are facing upwards. The CLK IN input of each WR-G65DDCe receiver within a coherent group must be connected to one of these ports using the SMA patch cables (for coherent clock distribution) supplied with the Kit and described in Section 2.2.2.
Section 3.4. Please note that, the 1PPS signal is not needed for coherent operation of the WR-G65DDCe receivers. The only purpose of the 1PPS signal is to provide a time base for the function of...
2.2.2). It distributes the 1PPS signal from the 1PPS IN input of the Coherent clock generator unit to all of the WR-G65DDCe receivers within a coherent group. If the 1PPS IN input is not used, the SYNC OUT can be left unconnected as well.
WR-G65DDCe Multichannel Coherent Application Guide 2.2.1.10 Power / Locked indicator The Power / Locked indicator is the blue color LED located on the front panel of the Coherent clock generator unit as shown in the Picture 2-4. It indicates whether the unit is powered as well as indicating the state of the internal oscillators.
CAUTION: For best performance and safety, we recommend using only the power adapter supplied by WiNRADiO, which comes included with your Coherent clock generator unit. Picture 2-5: The Power input socket of the Coherence clock generator unit located on the...
There are seventeen SMA patch cables supplied with the Kit. Eight of these SMA patch cables are used to distribute the sampling clock from the Coherent clock generator unit to all of the WR-G65DDCe receivers which are in coherent operation as described in Section 3.1.
Coherent clock generator unit. A minimum of two WR-G65DDCe receivers can be connected as a coherent pair, so six terminators are needed to terminate the sampling clock outputs. The seventh terminator is provided in case the external reference is used with the Coherent clock generator unit.
WR-G65DDCe Multichannel Coherent Application Guide Picture 2-9: SMA terminator (marked in red) factory pre-installed on the secondary sampling clock oscillator output 2.2.5 SMA jumper cable and the factory pre-installed LO OUT to CLK IN interconnection The Kit comes with an SMA jumper cable used to connect the primary sampling clock oscillator output LO OUT to the sampling clock oscillator input CLK IN.
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WR-G65DDCe Multichannel Coherent Application Guide Picture 2-10: Factory pre-installed SMA jumper cable (marked in red) interconnecting the LO OUT sampling clock oscillator output with the CLK IN sampling clock oscillator input. Please note the mandatory terminator installed on the other unused LO OUT...
The basic setup of eight receivers is shown in Picture 3-1. The setup consists of a minimum two and up to eight WR-G65DDCe/CR receivers connected to the PC through the USB3 port. The receivers are interconnected with the Coherent clock generator unit through their CLK IN port and also with each other through their SYNC IN and SYNC OUT ports in a daisy-chain like manner to allow for digital synchronization.
All cables used for clock distribution must be of the same type and length. Cables of various types and lengths cannot be used within one coherent group of receivers. For interconnection, only use the original WiNRADiO SMA patch cables supplied with the Clock Kit as these are specially matched to be coherent.
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WR-G65DDCe Multichannel Coherent Application Guide All receivers within one coherent group are equal from the clock distribution point of view. The number of the receivers which can be coherently clocked by one Coherent clock generator unit is up to eight. Two units can be linked for driving up to sixteen receivers as described in Chapter 4.
The number of the receivers which can be synchronized is unlimited in theory, but currently it is limited to 16. If more than sixteen channels are required, please contact WiNRADiO. Each SMA patch cable delays the synchronization signal by a certain time. The delay value is an integer number, which specifies the amount of sampling clock periods by which the cable delays the signal.
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WR-G65DDCe Multichannel Coherent Application Guide Picture 3-4: The SYNC interconnection is made in a daisy-chain manner, always linking SYNC OUT of the previous receiver with the SYNC IN of next receiver. The SMA patch cables described in Section 2.2.2 must be used for the interconnection. Only the SYNC...
WR-G65DDCe Multichannel Coherent Application Guide 3.3 Choosing the frequency reference When using the internal frequency reference, please connect the internal reference output REF OUT of the Coherent clock generator unit to the frequency reference input REF IN of the unit as shown in Picture 3-5. Please use the Frequency reference SMA interconnect cable as described in Section 2.2.3.
WR-G65DDCe Multichannel Coherent Application Guide 3.4 Using the 1PPS signal The 1PPS signal is not needed for coherent operation of the WR-G65DDCe receivers. However, if a function of time stamping is required, the user has to provide the 1PPS signal from a GPS receiver or similar timing source.
Section 2.2.1.9. CAUTION: For best performance and safety, we recommend using only the power adapter supplied by WiNRADiO, which comes included with the Coherent clock generator unit. 3.6 Finishing the installation of the receivers Finish the installation of the receivers by connecting the power adapter to each receiver and USB3 connection to the PC followed by installation of the device drivers and the standard receiver application.
To install more than eight and up to sixteen receivers as a single coherent group, two WiNRADiO Coherence Clock & 1PPS Kits (WR-CC1PPS-210e as described in chapter 2.2) are needed. Two coherent clock generator units are interconnected and act as single coherent clock generator unit providing 16 outputs of the coherent sampling clock.
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WR-G65DDCe Multichannel Coherent Application Guide No other ports on the slave unit are utilized in this extended installation. The ports REF IN, REF OUT, 1PPS IN, SYNC OUT as well as both LO OUT ports on a slave unit have to be left unconnected.
WR-G65DDCe Multichannel Coherent Application Guide Picture 4-2: The terminator for disabling the sampling clock oscillator is installed on the LO OFF port on the slave unit 4.2 Installation of receivers For installation of up to sixteen receivers please refer to Picture 4-3 and Chapter 3 of this document.
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WR-G65DDCe Multichannel Coherent Application Guide Picture 4-3: Sampling clock and digital sync signal interconnection of sixteen WR-G65DDCe receivers...
The standard installation of the WR-G65DDCe receivers in the coherent mode requires all receivers within the same coherent group to be connected to the same PC as shown in Picture 5-1.
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WR-G65DDCe Multichannel Coherent Application Guide The purpose of the ETC configuration is to allow for implementation of advanced parallel computing algorithms for phase-coherent systems as parallel multi-frequency and / or super- resolution estimation of direction of arrival, multi-frequency beam-forming and other applications requiring coherent reception of radio signals and their computation intensive processing.
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