IEEE GEOSCIENCE AND REMOTE SENSING SOCIETY SECTION
Recei ed 16 Janua y 2025, accep ed 18 Feb ua y 2025, da e o publica ion 27 Feb ua y 2025, da e o cu en e sion 4 Ap il 2025.
Digi al Objec Iden i ie 10.1109/ACCESS.2025.3546358
An SDR-Based GNSS-R CubeSa Payload:
Ha dwa e De elopmen and Op imiza ion
o he Onboa d P ocessing
SHAH ZAHID KHAN 1, (S uden Membe , IEEE), YASIR M. O. ABBAS 1, (Membe , IEEE),
EDWAR EDWAR 1, (S uden Membe , IEEE), ABDUL-HALIM JALLAD 1, (Membe , IEEE),
AND ADRIANO CAMPS 2,3,4, (Fellow, IEEE)
1Depa men o Elec ical and Communica ion Enginee ing, College o Enginee ing, Uni ed A ab Emi a es Uni e si y, Al Ain, Uni ed A ab Emi a es
2CommsSensLab-UPC, Depa men o Signal Theo y and Communica ions, Uni e si a Poli ècnica de Ca alunya-Ba celonaTech, 08034 Ba celona, Spain
3Ins i u d’Es udis Espacials de Ca alunya—IEEC, CTE-UPC, 08034 Ba celona, Spain
4ASPIRE Visi ing In e na ional P o esso , College o Enginee ing, Uni ed A ab Emi a es Uni e si y, Al Ain, Uni ed A ab Emi a es
Co esponding au ho : Abdul-Halim Jallad ([email p o ec ed])
This wo k was suppo ed in pa by ASPIRE ViP21-004 g an ; and in pa by Uni ed A ab Emi a es Uni e si y (UAEU).
ABSTRACT Recen de elopmen s in high-pe o mance So wa e De ined Radios (SDRs) and hei u i-
liza ion in CubeSa payloads a e ans o ming Ea h Obse a ion (EO), including Mic owa e Radiome e s,
Global Na iga ion and Sa elli e Sys em – Radio Occul a ions (GNSS-RO), and – Re lec ome y (GNSS-R).
In ecen yea s, GNSS-R has been inc easingly used in land and ma ine en i onmen al moni o ing, wi h
applica ions expanding o o he eme ging ields in EO. The so called Delay Dopple Map (DDM) is he
p ima y obse able o GNSS-R ecei e s, p o iding in o ma ion on su ace p ope ies, i.e. dielec ic cons an
and su ace oughness. E icien on-boa d p ocessing is essen ial in CubeSa -based GNSS-R missions, due o
he la ge olume o aw da a and he cons ain s o limi ed downlink bandwid h. Howe e , limi ed on-boa d
compu a ional esou ces p esen challenges, as DDM gene a ion equi es in ensi e Fas Fou ie T ans o m
(FFT) ope a ions. This s udy p esen s he design and de elopmen o a cos -e ec i e and compac 0.5U
GNSS-R CubeSa payload ha op imizes he GNSS-R da a p ocessing echnique by using he auxilia y
da a om he e e ence signals, such as Pseudo-Random Noise (PRN) codes, and hei Dopple equencies
in o de o educe he sea ch space. This way he payload selec i ely p ocesses he aw da a, signi ican ly
educing he compu a ional load. The payload p ocessing uni is implemen ed in Analog De ices ADRV9364
wi h a dual-co e ARM Co ex-A9 p ocesso wi h a Zynq-7000 Field-P og ammable Ga e A ay (FPGA).
INDEX TERMS CubeSa s, delay Dopple map (DDM), GNSS-R, in e e ome y, op imiza ion,
e lec ome y, so wa e de ined adios (SDRs).
I. INTRODUCTION
The minia u iza ion o elec onic componen s o e ecen
decades has d i en signi ican ad ancemen s in CubeSa
echnology, es ablishing hese small, modula sa elli es as
essen ial ools in EO. CubeSa s’ a o dabili y and expanded
access o space ha e led o widesp ead adop ion in bo h
scien i ic and comme cial missions [1]. Despi e hei compac
The associa e edi o coo dina ing he e iew o his manusc ip and
app o ing i o publica ion was Ge a do di Ma ino .
size, CubeSa s p o ide high scalabili y, as de elopmen
cycles, and modula designs wi h s anda d ‘‘uni s’’ (1U)
measu ing 10 ×10 ×10 cm3, allowing hem o pe o m
di e se asks e ec i ely, while hei lowe cos allows o
launch cons ella ions ha allow high empo al and spa ial
esolu ions. The use o SDRs p o ides a lexible a chi ec-
u e capable o ope a ing ac oss a ious equencies. This
makes hem a p e e ed choice o communica ions and
EO missions, including hose le e aging GNSS Signals o
Oppo uni y (SoOP).
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S. Z. Khan e al.: SDR-Based GNSS-R CubeSa Payload: Ha dwa e De elopmen and Op imiza ion
FIGURE 1. Payload block diag am.
A. GNSS: AN OVERVIEW
In GNSS-R, signals om GNSS sa elli es ha a e e lec ed
o he Ea h’s su ace a e hen ecei ed by dedica ed
ins umen s. This echnique, ini ially p oposed by Hall and
Co dey e al. in 1988 [2], and hen e ined o e he
yea s, le e ages on hese e lec ions o measu e a ious
su ace pa ame e s, including soil mois u e, sea s a e, and ice
co e [3].
In he so called con en ional GNSS-R (cGNSS-R) ech-
nique, he e lec ed signal (SR( )) is c oss-co ela ed wi h
a locally gene a ed eplica o he ansmi ed GNSS signal
(a( )) ac oss a ious delays and (τ) Dopple equency shi s
( d). Ma hema ically, his p ocess is exp essed as [4]:
Yc( 0, τ, d)=1
TcZ 0+Tc
0
SR( )a∗( −τ)e−j2π( c+ d) d ,
(1)
whe e:
• 0is he s a ime o he in eg a ion in e al.
•Tcis he in eg a ion pe iod, which ypically equals o he
du a ion o he pseudo- andom signal being used (e.g.
1 ms o GPS C/A code), o a mul iple o i , and
• cbeing he ca ie equency.
Due o he gene ally low ampli ude o Yc, and low Signal-
o-Noise Ra io (SNR), incohe en a e aging o e Niin e als
o du a ion equal o Tcis pe o med o imp o e he signal
quali y [4],[5]:
DDM( 0, τ, d)=1
Ni
Ni−1
X
n=0
|Yc( 0+n·Tc, τ, d)|2.(2)
The esul is he so-called DDM, which is he p ima y
obse able in GNSS-R ecei e s. The DDM ep esen s he
powe o he e lec ed signals as a unc ion o bo h he delay
and he Dopple equency shi , which a e ela ed o he
loca ions whe e he e lec ions ake place o e ing a de ailed
iew o su ace e lec ion cha ac e is ics.
B. GNSS-R-BASED CUBESAT MISSIONS AND DATA
PROCESSING CHALLENGES
La ge-scale and comme cial GNSS-R missions such as
he UK’s Disas e Moni o ing Cons ella ion-1 (DMC-1),
launched in 2003, se ed as a pionee ing In-o bi Demon-
s a ion (IoD) o a GNSS-R ins umen [6]. Subsequen
missions such as TechDemoSa -1 (TDS-1), de eloped by
Su ey Sa elli e Technology Limi ed (SSTL), was launched
in 2014 and ea u ed he Space GNSS Recei e Remo e
Sensing Ins umen (SGR-ReSI) [7]. NASA’s Soil Mois u e
Ac i e Passi e (SMAP) mission ollowed in 2015, u ilizing
GNSS-R o soil mois u e and eeze- haw s a e measu e-
men s [8]. The Cyclone Global Na iga ion Sa elli e Sys em
(CYGNSS) mission, launched in 2016, ma ked a signi ican
miles one as a la ge -scale cons ella ion designed o s udy
opical cyclones [9]. Mo e ecen ly, he BuFeng-1 (BF-1)
mission, a win sa elli e sys em launched in 2019, pe o med
obse a ions o he sea and he land su ace, including soil
mois u e [10],[11]. Ano he no able mission is he Spi e
Global 3U sa elli e cons ella ion, which in eg a es GNSS-R
capabili ies in some o i s sa elli es [12],[13].
These ea lie GNSS-R missions ini ially elied hea ily
on g ound-based p ocessing, bu la e inco po a ed on-boa d
p ocessing s a egies, enabled by ha dwa e and so wa e
op imiza ion ad ances. Fo example, ins umen s in [7],
highligh ed le e aging ac o s such as he geome y o he
ecei e and he size o he su ace sca e ing a ea o op imize
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S. Z. Khan e al.: SDR-Based GNSS-R CubeSa Payload: Ha dwa e De elopmen and Op imiza ion
da a handling. CYGNSS unde sco es he g owing emphasis
on on-boa d p ocessing, d i en by cons ain s such as limi ed
downlink bandwid h and as e da a deli e y [14]. On-boa d
p ocessing becomes pa icula ly c i ical in smalle CubeSa
missions, whe e size and powe limi a ions equi e e icien
use o compu a ional esou ces.
Fu he mo e, only a ew o he GNSS-R ins umen s ha e
been de eloped o nanosa elli es [15],[16],[17]. In [15]
he 3Ca -2 mission, which was 6U CubeSa , de eloped a
Uni e si a Poli écnica de Ca alunya (UPC) as an educa ional
p ojec , is discussed. On-boa d he mission was he PYCARO
(P(Y) and C/A Re lec ome e ), which implemen ed he con-
en ional and econs uc ed code echniques [18]. I aimed
o pe o m ocean al ime y and is cu en ly inac i e. In [16],
he 3Ca -4 sa elli e, a 1U CubeSa wi h a simila mission is
discussed, which encoun e ed a sola panel echnical ailu e
sho ly a e launch. In [17] he FMPL-2 ins umen lew on-
boa d 3Ca - 5/A, as pa o he FSSCAT mission, ESA S3
winne o he Cope nicus Mas e s’ 2017 Compe i ion. The
FMPL-2 is a combined L-band mic owa e adiome e and
GNSS-R ins umen . This mission p o ided soil mois u e, sea
ice ex en and co e age, and sea salini y maps. Mo eo e ,
in [5], PRETTY a 3U CubeSa payload u ilizing an SDR
is p esen ed. This Eu opean Space Agency (ESA) mission
aims o demons a e GNSS-R al ime y and sea ice de ec ion
applica ions.
The u u e o GNSS-R-based emo e sensing using
nanosa elli es is highly p omising, d i en by ad ancemen s
in minia u ized payloads, enhanced onboa d p ocessing
algo i hms, and he deploymen o la ge-scale sa elli e
cons ella ions. One signi ican ecen de elopmen is he
Tianmu-1 cons ella ion, which ep esen s a majo s ep
o wa d in using nanosa elli es o Ea h emo e sensing.
These de elopmen s a e expec ed o g ea ly enhance he
empo al and spa ial esolu ion o GNSS-R da a, enabling
mo e p ecise moni o ing o c i ical en i onmen al pa ame e s
such as soil mois u e, ocean su ace winds, and sea ice ex en .
Fu he mo e, he cos -e ec i eness, scalabili y, and apid
deploymen o nanosa elli es make hem an ideal solu ion
o global and con inuous Ea h moni o ing, add essing he
limi a ions o adi ional emo e sensing pla o ms.
While nanosa elli es a e ins umen al o GNSS-R mis-
sions, hey come wi h ade-o s, especially ega ding
on-boa d p ocessing and limi ed downlink capabili ies.
To add ess hese challenges, GNSS-R ecei e s can le e age
on auxilia y da a ob ained om he e e ence signal, such as
he PRN codes and he Dopple equencies o he signals
om he sa elli es in iew. This way, he Dopple equency
sea ch ange can be educed o a ew kHz. This app oach
op imizes he DDM gene a ion, educing he demands o
compu a ionally ex ensi e FFT calcula ions.
Following his app oach, his pape p esen s he de elop-
men o an SDR-based GNSS-R payload o CubeSa s in a
compac 0.5U o m ac o . Sec ion II discusses he design o
he payload, co e ing bo h ha dwa e and so wa e aspec s.
Sec ion III p esen s he expe imen al esul s and e alua es
ins umen pe o mance. Sec ion IV p o ides concluding
insigh s including po en ial u u e esea ch di ec ions.
II. HARDWARE AND SOFTWARE DESIGN
The de eloped GNSS-R ins umen u ilizes a Comme cial
O -The-Shel (COTS) FPGA-based SDR in eg a ed wi h
a cus om-designed in e ace boa d and a Radio F equency
F on -End (RF-FE) module. Figu e 1shows he block
diag am o he design. Each componen o he design is
discussed in de ail he ea e .
A. SDR
The SDR u ilized is he ADRV9364 om Analog De ices
wi h Sys em-on-Chip (SoC) a chi ec u e. I ea u es a com-
pac design, wi h dimensions o 100 ×66 mm2, and in eg a es
a single anscei e channel o RF ope a ions [19]. The co e
o he SoC is a high-pe o mance dual-co e ARM Co ex-A9
p ocesso in eg a ed wi h he ha dwa e p og ammable FPGA
(Zynq-7000), unning a Linux ope a ing sys em op imized o
embedded sys ems. This se up acili a es he implemen a ion
o he cus om-de eloped Py hon-based GNSS-R ecei e and
addi ional suppo ing sc ip s. To unc ion au onomously, he
SoC equi es a connec ion o an in e ace boa d, which
enables debugging, es ing, and da a s eaming.
B. INTERFACE BOARD
The in e ace boa d is a cus om-designed PCB ha se es as
he p ima y managemen and con ol uni o he GNSS-R
payload. I p o ides a physical in e ace o he SDR,
houses he digi al componen s, and in eg a es essen ial
powe , con ol, and s o age elec onics. The boa d includes
a se ial communica ion po wi h a empo a ily ins alled
E he ne po o es ing and debugging, which will be
emo ed la e in he ligh model. Figu e 2shows he
in e ace boa d de eloped, ha ing he PC104 o m ac o ,
wi h c ucial componen s and unc ionali ies ha suppo
payload ope a ions:
•In e ace: Facili a es he connec ions be ween he SDR
and he CubeSa ’s On-Boa d Compu e (OBC).
•Powe Supply: Dis ibu es dedica ed powe o he SDR,
digi al componen s, and RF boa d.
•Mic ocon olle (MCU): Se es as he p ima y com-
mand and con ol uni .
•S o age: P o ides sha ed memo y o DDMs, accessible
by he MCU, SDR, and he OBC.
•Ex e nal Clock: Supplies p ecise and s able clocks o
he mic op ocesso and SDR o accu a e GPS signal
p ocessing.
C. RADIO FREQUENCY FRONT-END
The RF-FE module consis s o ampli ie s, il e s, and
swi ches, se ing as he Signal Condi ion Uni (SCU) o
bo h he zeni h and nadi -looking sides. I is designed
wi h a double-s age low-noise ampli ie o achie e he
equi ed signal gain o he e lec ed GNSS signals. I also
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S. Z. Khan e al.: SDR-Based GNSS-R CubeSa Payload: Ha dwa e De elopmen and Op imiza ion
FIGURE 2. In e ace boa d o he GNSS-R payload.
inco po a es a high dynamics GNSS ecei e connec ed o he
e e ence signal (zeni h-looking an enna).
In addi ion o i s p ima y unc ion as an SCU, he uni can
swi ch i s ou pu be ween wo o ien a ions – zeni h and nadi
sides – based on a con ol signal ecei ed om he in e ace
boa d. Fu he mo e, each b anch includes wo in e nal loads:
an Ac i e Cold Load (ACL), a Ma ched Load (ML), and
a empe a u e senso o pe iodic calib a ion o gain and
noise igu e d i s [20]. Figu e 3p esen s he RF-FE boa d,
designed o align wi h he dimensions o he in e ace boa d.
Figu e 4illus a es he RF-FE ecei ing chain and de ails
FIGURE 3. RF-FE PCB o he GNSS-R payload.
FIGURE 4. O e iew o he RF-FE ecei ing chain.
he signal ou ing pa hs o he zeni h and nadi -looking
channels.
D. ANTENNAS
A Righ -Hand Ci cula ly Pola ized (RHCP) ac i e pa ch
an enna is used on he zeni h side. On he nadi side,
a ou -elemen Le -Hand Ci cula ly Pola ized (LHCP) pa ch
an enna a ay will be used. The design combines a pa ch
an enna on one side and sola cells on he o he side
on a deployable panel. The ou -pa ch a ay enhances he
pe o mance and inc eases he o e all gain. The an ennas
PCB is a ou -laye s ack designed o ensu e low losses and
p ope ma ching o all RF componen s. Figu e 5depic s
an a is ’s iew o he pa ch an enna a ay in i s deployed
con igu a ion on a 1U CubeSa , achie ing a o al gain o
≈12.9 dBi.
FIGURE 5. Deployable nadi -looking ou -elemen LHCP pa ch an enna
a ay o he GNSS-R payload.
E. GNSS-R RECEIVER
The GNSS-R ecei e u ilized in his s udy le e ages on
echniques employed in p e ious CubeSa missions de el-
oped by he UPC NanoSa Lab. A new co e design based
on a Py hon-sc ip ed ecei e unning on an SDR-hos ed
Linux en i onmen has been implemen ed. This cGNSS-R
ecei e in eg a es Py hon-based blocks om he GNU Radio
Companion (GRC) [21] o cap u e he aw In-phase and
Quad a u e (I/Q) GPS L1 da a.
An addi ional pa sing sc ip embedded wi hin he GNSS-R
ecei e e ches he auxilia y in o ma ion da a om a
high-dynamics GNSS ecei e housed in he same RF-FE
module.
F. PAYLOAD CONTROLLER
The Payload con ol sc ip se es as he cen al command and
con ol o he payload. I manages a ious asks, including:
•Powe Cycling: Tu ning payload modules such as he
SDR on and o .
•Da a S o age: Sa ing gene a ed DDMs o a local
memo y.
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S. Z. Khan e al.: SDR-Based GNSS-R CubeSa Payload: Ha dwa e De elopmen and Op imiza ion
FIGURE 6. (a) In eg a ed payload excep o he nadi - acing LHCP pa ch a ay, and (b) Block diag am o he payload s ack.
•Communica ion and Coo dina ion: Facili a ing he
OBC in o wa ding da a upon eques .
•RF-FE Con ol: Sending con ol signals o he RF-FE
o swi ch be ween zeni h and nadi b anches and ACL
and ML o calib a ion pu poses.
G. INTEGRATION OF THE PAYLOAD
The in eg a ed ha dwa e componen s a e shown in Fig. 6a.
In his s acked con igu a ion, he SDR is posi ioned on op,
ollowed by he in e ace boa d in he middle, and he RF
boa d a he bo om, as depic ed in Fig. 6b.
The o e all ope a ion o he payload is depic ed in he low
g aph p esen ed in Fig. 7.
FIGURE 7. O e iew o he GNSS-R payload’s ope a ion.
III. EXPERIMENTAL RESULTS AND DISCUSSION
Each payload module, including he in e ace boa d and
he RF-FE, ha e been indi idually es ed o unc ional-
i y and pe o mance. The ollowing sec ions de ail hese
e alua ions.
A. PERFORMANCE ANALYSIS OF THE RF-FE
Tes s on he manu ac u ed RF-FE module con i med he
equi ed signal gain and demons a ed p omising pe o -
mance. Figu e 8shows he measu ed equency esponses
o he zeni h and nadi channels, achie ing signal gains
o ≈30 dB.
FIGURE 8. Measu ed equency esponse o he zeni h-looking b anch o
he RF-FE.
B. EVALUATION OF THE HIGH-DYNAMICS OPERATION
CAPABILITIES OF THE GNSS RECEIVER
The LabSa GNSS simula o [22] was used o simula e
a high-dynamic Low-Ea h O bi (LEO) en i onmen o
assess he GNSS ecei e pe o mance o he P ecise
O bi De e mina ion (POD) and he DDM acking. The
es esul s con i med ha he GNSS ecei e eliably
locked on o he GPS L1 signal by u ilizing he zeni h
b anch o he RF-FE, con i ming he ecei e ’s obus
acking abili y in high-dynamic condi ions ypical o LEO
missions.
C. GNSS-R RECEIVER PERFORMANCE
The DDM gene a ion capabili ies o he GNSS-R ecei e
we e es ed by injec ing LabSa ’s syn he ic da a in di e se
se ings, including s a ic, low-dynamic, ai bo ne, and
high-dynamic spacebo ne scena ios. Figu e 9p esen s a
gene a ed DDM, highligh ing a dis inc co ela ion peak
achie ed wi h 1 ms o cohe en and Ni =500 incohe en
in eg a ion. The ade-o be ween cohe en and incohe en
in eg a ion imes signi ican ly impac s he DDM’s spa ial
esolu ion, in luencing he Dopple equency esolu ion, and
along- ack blu ing [23].
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TABLE 1. GNSS-R p ocessing me ics be ween ull sa elli e se , a ge ed PRN codes, and a ge ed PRN codes wi h educed dopple sea ch ange.
FIGURE 9. The sample gene a ed DDM by he GNSS-R ecei e .
D. GNSS-R PROCESSING IMPROVEMENT BY USING
AUXILIARY INFORMATION
The GNSS-R ecei e le e ages on auxilia y pa ame e s
ex ac ed om he Zeni h-looking POD GNSS ecei e o
enhance he p ocessing e iciency. This e e ence signal
in o ma ion includes he PRN code numbe o he sa elli es
in iew wi h he s onges signals and/o wi hin a ce ain
ele a ion angle. This limi s he DDM gene a ion o hese
speci ic PRN codes only, signi ican ly educing he GNSS-R
ecei e ’s compu a ional bu den. Fu he enhancemen s we e
achie ed by inco po a ing Dopple equency shi in o -
ma ion o he selec ed PRN codes. This in o ma ion helps
na ow he Dopple equency sea ch ange a ound he
DDM peaks, educing he FFT p ocessing equi emen s
o gene a ing a DDM. Table 1p esen s ha combined
op imiza ion i.e. educing he numbe o PRN codes and
na owing he Dopple sea ch ange, esul ed in a signi ican
cumula i e p ocessing op imiza ion imp o emen by an
≈99% educ ion in o al execu ion ime, an ≈87% educ ion
in I/O ead ope a ions, and ≈98% educ ion in I/O w i e
ope a ions.
This op imiza ion acili a es he on-boa d p ocessing by
signi ican ly educing he compu a ional demands, which
is c ucial gi en he limi ed p ocessing powe a ailable
on-boa d. Addi ionally, i educes he da a ans e equi e-
men s o g ound p ocessing by gene a ing compac DDMs
ins ead o equi ing la ge olumes o aw da a o be
downloaded.
IV. CONCLUSION
In CubeSa s-based GNSS-R missions, e icien on-boa d
da a p ocessing is c ucial due o limi ed compu a ional
esou ces and he limi ed downlink capabili ies. This s udy
has p esen ed he design and de elopmen o a 0.5U
GNSS-R payload wi h op imized DDM gene a ion, u ilizing
auxilia y in o ma ion ob ained om he e e ence signal
o acili a e he on-boa d p ocessing. The de ails o he
de eloped ha dwa e and so wa e ha e been p esen ed. The
es s demons a ed ha in he GNSS-R ecei e , p ocessing
e iciency was enhanced by ≈99% in case 4 ou o he 32 PRN
Codes we e a ailable in he e lec ed signal, h ough he
u iliza ion o auxilia y in o ma ion on he e e ence signal,
such as he a ailable PRN codes and hei Dopple equency,
due o he a ge ed DDM gene a ion o he PRN codes
and hei educed Dopple sea ch bin while p ocessing he
aw da a. Fu he mo e, he in eg a ed ha dwa e was es ed
o p ocess GNSS-R da a in a simula ed high-dynamics
en i onmen as in a LEO, demons a ing he po en ial o
eliable ac ual ope a ion.
Fu he mo e, se e al challenges ela ed o he ha dwa e
and echniques u ilized ha e been iden i ied. One key
challenge is ensu ing he compa ibili y o he SDR o m
ac o wi hin he CubeSa s anda d. Al hough he payload
is designed o i wi hin a 1U CubeSa , he SDR module
sligh ly p o udes beyond he s anda d PC/104 boa d ails.
To add ess his, a speci ic s uc u e will ha e o be
conside ed o imp o ed in eg a ion. Ano he conside a ion
in ol es u he op imizing he GNSS-R da a p ocessing by
le e aging on he FPGA’s capaci y o handle da a-in ensi e
ope a ions such as he FFT compu a ion independen ly o
he so wa e laye . O -loading he FFTs o he FPGA
componen o he SDR will allow o compu e mo e DDMs pe
second.
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SHAH ZAHID KHAN (S uden Membe , IEEE)
ecei ed he deg ee in elec onics enginee ing
om Ka achi Ins i u e o Economics and Tech-
nology (KIET) and he M.Sc. deg ee in a ionics
enginee ing om he Na ional Uni e si y o Sci-
ences and Technology (NUST), Pakis an. He is
cu en ly pu suing he Ph.D. deg ee wi h Uni ed
A ab Emi a es Uni e si y (UAEU), specializing in
GNSS- e lec ome y payloads and da a p ocessing
echniques. His esea ch in e es s include GNSS
secu i y, d one na iga ion sys ems, GNSS-R, and small sa elli e sys ems.
He is cu en ly pa o he Remo e Sensing Labo a o y (RSL), UAEU.
He has been ac i ely in ol ed in p ojec s ela ed o GNSS-R payloads
and syn he ic ape u e ada (SAR) and has au ho ed o co-au ho ed
se e al a icles in pee - e iewed jou nals and con e ences. In 2024,
hei eam was hono ed wi h he Bes Pape Awa d o inno a i e
esea ch in space echnologies a he Space Resea ch Con e ence,
UAE.
YASIR M. O. ABBAS (Membe , IEEE) was
bo n in Sudan, in 1988. He ecei ed he B.Sc.
deg ee in elecommunica ions enginee ing om
he Uni e si y o Kha oum, Sudan, in 2010,
he M.Sc. deg ee in ae ospace enginee ing om
Is anbul Technical Uni e si y (ITU), Tü kiye,
in 2015, and he Enginee ing Doc o a e deg ee
in embedded sys ems and space enginee ing om
Kyushu Ins i u e o Technology (Kyu ech), Japan,
in 2021. He is cu en ly a Pos doc o al Resea che
wi h UAE Uni e si y, Al Ain, Uni ed A ab Emi a es. He has been ac i ely
in ol ed in he de elopmen o CubeSa s, ocusing on mic owa e emo e
sensing sa elli e missions, elecommunica ion subsys ems, and on-boa d
compu e s. His esea ch in e es includes a ound sa elli e enginee ing, wi h
a pa icula emphasis on he design and implemen a ion sys ems o space
applica ions.
VOLUME 13, 2025 56051
S. Z. Khan e al.: SDR-Based GNSS-R CubeSa Payload: Ha dwa e De elopmen and Op imiza ion
EDWAR EDWAR (S uden Membe , IEEE)
ecei ed he bachelo ’s deg ee in elecommu-
nica ion enginee ing om Telkom Uni e si y
and he mas e ’s deg ee om Bandung Ins i u e
o Technology. He is cu en ly pu suing he
Ph.D. deg ee in elec ical and communica ion
enginee ing wi h he College o Enginee ing,
Uni ed A ab Emi a es Uni e si y (UAEU). He is
cu en ly an Assis an P o esso wi h he School o
Elec ical Enginee ing, Telkom Uni e si y, whe e
his esea ch ocuses on nanosa elli e subsys ems and payload de elopmen ,
ada ins umen a ion, an ennas, and RF de ices. He is also a membe o
he Remo e Sensing Labo a o y (RSL). His doc o al esea ch is cen e ed
on P-band ada de elopmen , con ibu ing o ad ancemen s in nanosa elli e
echnology, and ada ins umen a ion.
ABDUL-HALIM JALLAD (Membe , IEEE)
ecei ed he B.Eng. deg ee in elec onics engi-
nee ing om he Uni e si y o Ken , U.K.,
in 2003, and he Ph.D. deg ee om Su ey Space
Cen e, Uni e si y o Su ey, U.K., in 2009.
His hesis ocused on ‘‘Dis ibu ed Compu ing
o Space-Based Wi eless Sa elli e Ne wo ks.’’
Cu en ly, he is an Associa e P o esso wi h he
Depa men o Elec ical and Communica ions
Enginee ing, Uni ed A ab Emi a es Uni e si y
(UAEU), and an A ilia e P o esso wi h he Na ional Space Science and
Technology Cen e , UAEU. P e iously, he has se ed in a ious academic
and leade ship oles a Ame ican Uni e si y o Ras Al-Khaimah and Al-
Zay oonah Uni e si y o Jo dan. His esea ch in e es s include ha dwa e
design o space sys ems, spacec a onboa d command and da a handling
sys ems, he IoT and wi eless senso ne wo ks, and e icien FPGA-based
designs. He has led nume ous p ojec s unded by p ominen o ganiza ions,
such as UAE Space Agency and ASPIRE UAE.
ADRIANO CAMPS (Fellow, IEEE) was bo n
in Ba celona, Spain, in 1969. He ecei ed he
deg ee in elecommunica ions enginee ing and
Ph.D. deg ee in elecommunica ions enginee ing
om he Uni e si a Poli ècnica de Ca alunya
(UPC), Ba celona, Spain, in 1992 and 1996,
espec i ely. In 1991 o 1992, he was a he ENS
des Télécommunica ions de B e agne, F ance,
wi h an E asmus Fellowship. Since 1993, he has
been wi h he Elec omagne ics and Pho onics
Enginee ing G oup, Depa men o Signal Theo y and Communica ions,
UPC, whe e he was a i s Assis an P o esso , an Associa e P o esso in
1997, and a Full P o esso since 2007. In 1999, he was on sabba ical lea e
a he Mic owa e Remo e Sensing Labo a o y, Uni e si y o Massachuse s,
Amhe s . Since 1993, he has been deeply in ol ed in he Eu opean Space
Agency SMOS Ea h Explo e Mission, om he ins umen and algo i hmic
poin s o iew, pe o ming ield expe imen s, and mo e ecen ly s udying
he use o GNSS-R echniques o pe o m he sea s a e co ec ion needed
o e ie e salini y om adiome ic obse a ions. His esea ch in e es s a e
ocused in mic owa e emo e sensing, wi h special emphasis in mic owa e
adiome y by ape u e syn hesis echniques and emo e sensing using
signals o oppo uni y (GNSS-R). His publica ion eco d includes o e 268
pape s in pee - e iewed jou nals, nine book chap e s, and he book Eme y
and Camps, ‘‘In oduc ion o Sa elli e Remo e Sensing: A mosphe e, Ocean,
Land and C yosphe e Applica ions,’’ Else ie , 2017, 860 pages), and mo e
han 541 con e ence p esen a ions. Acco ding o Google Schola , his h-
index is 66, and his publica ions ha e ecei ed mo e han 17338 ci a ions.
Acco ding o he Oc obe 2023 S an o d anking, he is among he op
2% o esea che s in all ca ego ies. He holds 12 pa en s and has ad ised
33 Ph.D. Thesis s uden s (+10 ongoing), and mo e han 150 B.Eng. inal
deg ee and M.Eng. Theses. These Ph.D. s uden s ha e now esponsibili y
posi ions a Uni e si ies, companies, and esea ch cen e s, including
NASA/JPL, ESA, and Ai bus and wo ha e s a ed hei own companies
wi h P o . Camps’ pa icipa ion, ha ing ans e ed a o al o i e pa en s
o hem.
56052 VOLUME 13, 2025
